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Essenrials of Medicinal Chemistry
... [5] It may also be used to cause memory loss during certain medical procedures. [6] [7] It can be taken by mouth, inserted into the rectum, injected into a muscle, or injected into a vein. [7] When given into a vein, effects begin in one to five minutes and last up to an hour. ...
... [6] [7] It can be taken by mouth, inserted into the rectum, injected into a muscle, or injected into a vein. [7] When given into a vein, effects begin in one to five minutes and last up to an hour. [7] By mouth, effects may take 40 minutes to begin. ...
... [7] When given into a vein, effects begin in one to five minutes and last up to an hour. [7] By mouth, effects may take 40 minutes to begin. [8] Common side effects include sleepiness and trouble with coordination. ...
ABSTRACT:
A major concern to the pharmaceutical industries is the quality of
pharmaceutical finished dosage forms. The development of any
pharmaceutical product is to maintain the quality standard of the
product which is an important aspect. Through a variety of directions,
pharmaceutical preparations take many shapes and forms and are well
organized. Oral solid dosage forms remarkably the tablet dosage form
is the most prominent of all. Many research studies and experiments to
maintain the proper quality standards of the tablet dosage form of any
pharmaceutical company has to go through a lot. To ensure quality
product different level of tests are done. Diazepam is a drug which has
effects on the central nervous system. The purpose of this study which is to investigate the
status of different brands of diazepam tablets are manufactured in Bangladesh and because of
this investigation the researchers find out that such tablets give better pharmacological action,
should not yield noxiousness and the universal image of a tablet, its apparent individuality,
and entire grace is requisite for consumer assent. Incompatible physical limitations such as
stiffness, expanse, frailty as well as dissolution time were led to assess the character of the
tablets of various brands of diazepam. The scale of the stiffness test result was 4.7-9.0 kg.
This research work was aimed to investigate the quality control parameters of five brands of
diazepam (Seduxen®, Sedil® D-Pam®, Evalin®, Easium®) which are available in the
market. This, in turn, helps to determine whether the five brands of diazepam were
manufactured according to the specifications given by British Pharmacopeia (BP). The five
brands of diazepam were collected from local market of Bangladesh. Then the brands were
subjected to physical parameter tests such as weight variation, hardness, thickness, friability,
and disintegration. The brands passed the tests as no tablets cross the ±7.5% weight variation.All the 50 tablets of both the brands disintegrated within 15 minutes and thus they complied
with the specifications. Last but not least it can be concluded that five brands of diazepam
were manufactured according to the specifications given by British Pharmacopeia (BP). we
have done other tests required for the determination of the quality control parameters which
have shown satisfactory results
... For background to the pharmacological uses of sulfonamides, see: Korolkovas et al. (1988); Mandell & Sande (1992). For the antifilarial activity of sulfonamide derivatives, see: Radembino et al. (1997); For related structures, see: Ranjith et al. (2009); Madhanraj et al. (2011). ...
... Sulfonamide drugs are widely used for the treatment of certain infections caused by Gram-positive and Gram-negative micro-organisms, some fungi, and certain protozoa (Korolkovas et al., 1988, Mandell & Sande 1992). One of the Sulfonamide derivatives (epoxysulphonamides and ethynesulphonamides) shows anti-filarial activity (Radembino et al., 1997). ...
In the title compound, C
26
H
25
NO
6
S, the S atom shows a distorted tetrahedral geometry, with O—S—O [119.46 (9)°] and N—S—C [107.16 (7)°] angles deviating from ideal tetrahedral values, a fact attributed to the Thorpe–Ingold effect. The sulfonyl-bound phenyl ring forms dihedral angles of 41.1 (1) and 83.3 (1)°, respectively, with the formylphenyl and phenyl rings. The dihedral angle between formylphenyl and phenyl rings is 47.6 (1)°. The crystal packing features C—H...O hydrogen-bond interactions.
... This paper belongs to Topical Collection MIB 2013 (Modeling Interactions in Biomolecules VI) Electronic supplementary material The online version of this article (doi:10.1007/s00894-014-2276-7) contains supplementary material, which is available to authorized users. of microenvironment acidity in the context of the variation in the protonic activity of p-aminosulfonamide (SNM) as a function of its polymorphic form and morphology was addressed. Although sulfonamide drugs have been somewhat superceded by antibiotics, they are still extensively used to treat certain infections caused by some fungi, protozoa, and both Grampositive and Gram-negative microorganisms [16, 17]. Sulfonamide drugs that act as antibacterial and antimicrobial agents inhibit bacterial growth and activity due to their ability to interfere with metabolic processes in bacteria. ...
... Sulfonamide drugs that act as antibacterial and antimicrobial agents inhibit bacterial growth and activity due to their ability to interfere with metabolic processes in bacteria. They are used in the prevention and treatment of bacterial infections, diabetes mellitus, edema, hypertension, and gout [17]. Sulfonamide derivatives are remarkably polymorphic18192021222324252627282930313233343536. ...
A new approach for estimating local basicities/acidities of groups exposed on crystal surfaces was formulated and validated. The model, constructed within a quantitative structure–property relationship (QSPR) framework, allowed the expression of the protonic properties of amine and sulfonamide groups as functions of simple molecular descriptors of geometric types. This enabled the application of a QM/MM approach for the structural optimization of SNM molecules located on the surfaces of the dominant crystal habits. The obtained pKa values were used for classification of the protonic properties of four p-aminosulfonamide (SNM) polymorphs. The computed distributions of the surface pKa values suggested that, for all polymorphs, the amino group has statistically the same proton-accepting ability on the crystal surface as in bulk water solution. Although sulfonamide groups on the crystal surface—especially those distributed on β- and γ-dominant faces—seem to be more acidic compared to bulk water solution, the pKa values are statistically indistinguishable irrespective of the morphology. This suggests that experimentally observed differences in the perichromic properties of SNM polymorphs do not arise from local pH changes, Thus, apparent local basicities are to be relaed to structural similarity of SNM surfaces and thymol blue conformers anabling direct interactions.
Figure
Experimentally observed differences in the perichromic properties of p-aminosulfonamide polymorphs are structural in origin; they are not due to local pH changes
Electronic supplementary material
The online version of this article (doi:10.1007/s00894-014-2276-7) contains supplementary material, which is available to authorized users.
... To understand the chemistry of biological system, it is important to study properties of amino acids in aqueous-drug solutions 4 . Most of the compounds of medicinal interest undergo a number of complicated interactions of varied nature 5,6 . Drug action has been widely recognized to be the ultimate consequence of physicochemical interactions between the drug and functionally important biomolecules in living organisms. ...
The Kirkwood-Buff (K-B) integrals play a pivotal role in
understanding the physiochemical action of drugs on proteins. The
Kirkwood-Buff theory can be used to characterize the
intermolecular interactions of amino acids with drug by directly
calculating G11, G22 and G12 parameters which represent solute�solute, solvent-solvent and solute-solvent interactions respectively.
The K-B integrals of nonpolar amino acids glycine, L-alanine,
L-valine, L-isoleucine and polar amino acids L-histidine and
L-arginine in aqueous-streptomycin sulphate solutions (1% and 2%
streptomycin sulphate in water, w/w) have been calculated from
experimental data of ultrasonic speed and density at 298.15 K. All
the results obtained by theoretical calculations are in good
agreement with those of experimental results.
... Malaria is caused by parasitic protozoa of the genus Plasmodium and it is transmitted to humans by the female Anopheles mosquitoes, which are present in almost all tropical and subtropical countries. There are approximately 380 Anopheles species, but only about 60 transmit malaria [4]. ...
... The substitution of the lead compound will result in changes in physicochemical properties, namely lyophilic, electronic, and steric characteristics [9]. To design and develop new drugs, the physicochemical properties of drug molecules can be predicted before a new compound is synthesized and purified. ...
1-(Benzoyloxy)urea and its derivatives were synthesized by modified Scotten-Bauman reaction with adding benzoyl chloride or homologs to hydroxyurea in tetrahydrofuran. Structure characterization was conducted based on ultraviolet (UV-VIS) spectrum, infrared (FT-IR), H nucleus magnetic resonance (1 H NMR), C nuclear magnetic resonance (13 C NMR) and mass spectrometry (MS). In silico test to predict anti-cancer activity of 1-(benzoyloxy)urea and its derivatives in ribonucleotide reductase enzyme (PDB: 2EUD) was done using Molegro Program. The anti-cancer activity test was performed in vitroby using MTT method to HeLa cell lines. In silico test result (Rerank Score) was correlated relative to anti-cancer activity (log1/IC 50). There was a significant linear relationship between in vitroand in silico anti-cancer activity.
... This diagram is based on the basic assumption of H?nsch's method that a particular substituent may alter the relative activity to the mother compound based on changes in the hydrophobic, electronic effects, and steric [8]. A substitution on the guiding compounds alters the physicochemical properties which include lipophilic, electronic, and steric properties [9]. Until now, researchers are still using the Topliss' diagram for designing a drug because the theory is found to be relatively understandable and easy to follow. ...
Drug development is originally carried out on a trial and error basis and it is cost-prohibitive. To minimize the trial and error risks, drug design is needed. One of the compound development processes to get a new drug is by designing a structure modification of the mother compound whose activities are recognized. A substitution of the mother compounds alters the physicochemical properties: lipophilic, electronic and
steric properties. In Indonesia, one of medical treatments to cure cancer is through chemotherapy and hydroxyurea. Some derivatives, phenylthiourea, phenylurea, benzoylurea, thiourea and benzoylphenylurea, have been found to be anticancer drug candidates. To predict the activity of the drug compound before it is synthesized, the in- silico test is required. From the test, Rerank Score which is the energy of interaction between the receptor and the ligand molecule is then obtained. Hydroxyurea derivatives were synthesized by modifying Schotten-Baumann’s method by the addition of benzoyl group and its homologs resulted in the increase of lipophilic, electronic and steric properties, and cytotoxic activity. Synthesized compounds were
1-(benzoyloxy)urea and its derivatives. Structure characterization was obtained by the spectrum of UV, IR, H NMR, C NMR and Mass Spectrometer. Anticancer activity was carried out using MTT method on HeLa cells. The Quantitative Structure-Cytotoxic Activity Relationships of 1-(benzoyloxy)urea compound and its derivatives was calculated using SPSS. The chemical structure was described, namely: ClogP, π, σ, RS, CMR and Es; while, the cytotoxic activity was indicated by log (1 / IC50). The results show that the best equation of Quantitative Structure-Cytotoxic Activity Relationships (QSAR) of 1- (benzoyloxy)urea compound and its derivatives is Log 1/IC50 = - 0.205 (+ 0.068) σ – 0.051 (+ 0.022) Es – 1.911 (+ 0.020).
... The dynamic response of the intermolecular hydrogen bonds to photoinduced changes of charge distribution in different electronic state is called as the hydrogen bonding dynamics which always occur on ultrafast timescale based on vibrational motion of the hydrogen bond donor and acceptor [12][13][14]. Recently, Zhao et al demonstrated that the hydrogenbonding dynamics in electronically excited states play an important role in many phenomena such as photoinduced electron transfer and fluo- rescence [15][16][17][18][19]. Hydrogen bonded charge transfer complexes received much interest in many fields as drug-receptors binding mechanism [20,21], surface chemistry [22], applications in solar energy storage [23], uses as organic superconductors [24], and in many biological fields as antibacterial and antifungal agents [25] . These complexes received also, many applications in analytical chemistry [26,27]. ...
... Since cellular growth arrest is usually focused on prevention of out-law replication of cellular DNA or RNA, potential antiviral and antitumor activities of several antimetabolites are not uncommon [18]. For this reason, the protocol involved in the presented work (Table 1) From consideration of the results listed in table1, it can be easily seen that most of the tested βcarbolines bearing varied levels of the antiviral estimations. ...
The in-vitro assessment of antiviral activity against Flu-A, HIV, RS, HSV type-1, HSV type-2, and HCMV provided
that β–carboline scaffold attach to alkyl substituted with oxo, oxy or polyoxy groups can be further developed as
antiviral and/or anticancer agents. Screening of the potential cytocidal properties using HL-200 and several other
cell-lines was also done.
... Essential hypertension affects about 10% of the world population and constitutes about 80% of the total cases of hypertension [1,2]. Satisfactory blood pressure control invariably requires chronic therapy, and the drug side effects must be minimal, consequently, clinical interest is improved and novel antihypertensive agents have been elaborated. ...
In this manuscript, we investigated-in vivo- the hypotensive activity of the new derivatives related to the scaffold pyrimido-benzimidazole and compared the results with tolazoline. All of the reference; tolazoline and the tested derivatives are introduced in equimolar ratios in doses of (0.1 mg/kg iv) using anaesthetized-normotensive nonhuman primates (dogs). The new pyrimido [l,2-a] benzimidazole derivatives were synthesized from 2,4-dimethylpyrimido [1,2-a] benzimidazole (1) which intern, obtained from condensing 2-aminobenzimidazole with acetylacetone. Precusor 1 was then condensed with the appropriate aldehyde 2a-f to produce two series: 3a-f, and 4a-f, as trans [E]-configurational geometry. The structure of the synthesized derivatives has been characterized by elemental microanalysis (CHN), IR, MS and NMR Spectroscopy, as well as physicochemical properties. In conclusion: Pyrimido-benzimidazole scaffold is a good target for antihypertensive activity.
... The study of charge transfer complex play a highly prominent role in biological systems, viz., analysis of some drugs, pharmaceutical preparations and also significant physical properties of the charge transfer products, such as, electrical conductivities and their applications in the field of photonic and solar cells4567 . Moreover, CT complexs play a very important task in many biological systems, such as DNA-binding, antibacterial, antifungal, insecticides as well as take part a vital role in the field of drug receptor binding mechanism due to the presence of aromatic electron donors and electron acceptors containing nitrogen, oxygen or sulphur atoms891011. Benzothiazole is an important heterocyclic compound having both nitrogen and sulphur. ...
... Essential hypertension affects about 10% of the world population and constitutes about 80% of the total cases of hypertension [1,2]. Satisfactory blood pressure control invariably requires chronic therapy, and the drug side effects must be minimal, consequently, clinical interest is improved and novel antihypertensive agents have been elaborated. ...
In this manuscript, we investigated-in vivo- the hypotensive activity of the new derivatives related to the scaffold pyrimido-benzimidazole and compared the results with tolazoline. All of the reference; tolazoline and the tested derivatives are introduced in equimolar ratios in doses of (0.1 mg/kg iv) using anaesthetized-normotensive nonhuman primates (dogs). The new pyrimido [l,2-a] benzimidazole derivatives were synthesized from 2,4-dimethyl-pyrimido [1,2-a] benzimidazole (1) which intern, obtained from condensing 2-aminobenzimidazole with acetyl-acetone. Precusor 1 was then condensed with the appropriate aldehyde 2a-f to produce two series: 3a-f, and 4a-f, as trans [E]-configurational geometry. The structure of the synthesized derivatives has been characterized by elemental microanalysis (CHN), IR, MS and NMR Spectroscopy, as well as physicochemical properties. In conclusion: Pyrimido-benzimidazole scaffold is a good target for antihypertensive activity.
Keywords: Hypotensive activity, Anaesthetized-normotensive dogs, Pyrimido-benzimidazoles, Regioselectivity, E-isomer, geometrical isomerism
... The antihypertensive activity of guanidine congeners; a structural feature recognized and optimized for their neuronal receptor binding in several drugs. The binding was generally enhanced by the hydrophobic ring attachments [1]. For revealing such activity, it was irrelevant to devote this to the synthesis of pyrimido [1,2-a] benzimidazole ring system which was recognized in literature since 1937 [2]. ...
In this work, we studied the in vivo pharmacological effects of the new derivatives related to fused [6-5-6] system, pyrimido-benzimidazole and compared with those of tolazoline. In anaesthetized normotensive dogs, both 6d and tolazoline (10-3 mmole/kg, iv) caused a pronounced fall in mean blood pressure as hypotensive agents. Upon investigating the antihypertensive activity of 6d, it markedly inhibited the hypertensive effect of noradrenaline. The required new pyrimido [l,2-a] benzimidazole derivatives were synthesized from precursors 1-3. Compounds 1-3 intern obtained from condensing 2-aminobenzimidazole with beta-diketones which were then condensed with the appropriate aldehyde 4a-f to produce three series: 5a-f, 6a-f and 7a-f. The products are obtained in moderate yields and are in trans [E]-configuration. The structure of the synthesized derivatives has been characterized by elemental microanalysis (CHN), IR and NMR Spectroscopy, as well as physicochemical properties. The geometry of the alkene resulted from condensation was verified by IR. In conclusion: Pyrimido-benzimidazole scaffold is a good target for further search for antihypertensive agents.
... Organic intermolecular charge transfer complexes have received a great deal of interest in recent years due to their potential applications in optical, magnetic, electrical and biological fields123456789. Charge transfer complexes also find application in the field of drug receptor binding mechanism due to the presence of aromatic electron donors and electron acceptors containing nitrogen, oxygen or sulfur atoms101112131415161718. These complexes are formed between an electron rich donor molecule with low ionization potential and an electron deficient acceptor molecule with high ionization potential [19]. ...
... Sulphonamides are known to represent a class of medicinally important compounds which are extensively used as antimicrobial , antimalarial, and anticancer agents and inhibitors of carbonic anhydrase among others [1, 2]. Before the discovery of antibiotics in the 1940s, sulphonamides were the first efficient compounds used to treat microbial infections [3]. ...
A new class of N-(heteroaryl-substituted)-p-toluenesulphonamides has been synthesized exhibiting antibacterial and antifungal properties. The condensation reaction of p-toluenesulphonyl chloride 1 with appropriate substituted amino pyridines 2a–g in acetone furnished N-(heteroaryl-substituted)-p-toluenesulphonamides 3a–g. These derivatives were characterized by IR, 1H-, and 13C-NMR spectroscopy and were screened in vitro against gram-positive bacteria, gram-negative bacteria, and fungi organisms using agar-diffusion method. Results indicated improved biological activities over reference drugs such as Tetracycline (TCN) and Fluconazole (FLU).
... There are four main species of the parasite (P. falciparum, vivax, ovale, and malariae) that are known to affect man [1]. Malaria caused by P. falciparum is the most deadly and prevalent (90% -98%). ...
Background: Widespread resistance has been recorded with the use of monotherapy in the management of malaria. In 2000, Ghana initiated the process of using Artemisinin-based combination therapy (ACT) following the World Health Organization’s (WHO) recommendation. Globally and in Ghana, there stands a high risk of development of resistance to the ACTs due to the act of counterfeiting or substandard drugs. In 2009, there was a report that fake Coartem, an ACT had been found in Ghana by the Drug Quality and Information (DQI) Program; this is a serious national problem that needs redress thus the need to conduct this study to check if there are any substandard or counterfeit Artemether/ Lumefantrine tablets on the Ghanaian market. Method: Using Representative sampling method, a total of nine different brands or samples of artemether/lumefantrine tablets were sampled from nine different Pharmacies in Accra. The samples were analyzed using a validated MVHimagePCv8.exe colour software technology. Results: The International Conference on Harmonization (ICH) and United States Pharmacopoeia (USP) recommend that for assay of tablets, the percentage concentration should fall within 80%-120%. After the analysis, seven out of the nine samples passed the test to varying degrees. Two samples (AL-S4 and AL-S6) however failed the test with AL-S4 recording artemether concentration (126.07%) above and Lumefantrine concentration (78.38%) below the recommended figure while AL-S6’s 51.53% failed to meet the minimum allowable concentration for lumefantrine in a tablet. Conclusion: The results presented show that some Artemether/Lumefantrine tablets on the Ghanaian market still have issues with regards to quality or level of active ingredients. There would therefore be the need for further studies to be conducted into these products especially those that failed the test.
... It is also observe that leaves of it are used extensively in folk medicine for decreasing sugar level of blood and showed significant anti-hyperglycemic effect. Due to medicinal virtues to this plant, it is used in Ayurvedic preparations for treating various diseases [1][2][3][4][5][6][7][8][9][10] . Recently in this laboratory enormous work on natural products was carried out by one research group of D.T.Tayade 11-19 especially on proximate, phytochemical, physiochemical and spectroscopical analysis of various plants and as a part of research work, presently being undertaken in this laboratory on natural products, hence it appeared sufficient interesting to carry out phytochemical analysis of the leaves of Catharanthus roseusA. ...
India is a rich storehouse of medicinal plants. All natural products can be termed bioactive molecules, as every diverse molecule possesses one kind or multiple kinds of biological oblique pharmacological activities. The beauty about Natural Products (Herbal Drugs) libraries is the uniqueness in their chemical structural diversity and innovativeness that in compasses varied biological actions. Herbal drugs played an important role in drug discovery and were the basis of most early medicines. The major role of this is also seen in ontological, antihypertensive, immunosuppression and metabolic diseases. Since ages passed over traditional systems of medicine have depended on natural products derived from plant sources. There is a tremendous historical legacy of folklore uses of the plants in medicine. They have been used for the treatment of diseases in almost all the ancient civilization. 80% world population for the health care throughout the world is used nearly only 4% medicinal plants, while only a small percentage of which have been chemically investigated. Today India is a formidable force in generic world pharmaceutical market in the last 20 years, Indian chemist have made great contribution in developing cutting edge technology of active pharmaceutical ingredients. Hence taking all these things into consideration it create sufficient interest to carry out phytochemical analysis of leaves of Catharanthus roseus A. from Benoda region, due to the important pharmaceutical and medicinal properties of Catharanthus roseus A.
... The sulfonamide derivatives are known for their numerous pharmacological activities, antibacterial, antitumor, insulin-release stimulation and antithyroid properties. The phenolic azo-dyes derived from the sulfonamides have the therapeutic potentialities and special mode of action against the acute bacterial infections [7]. Some benzenesulfonamides are evaluated for their in vitro antitumor activity [8]. ...
... Electron donor D and electron acceptor A to involve charge transfer interaction within a molecular complex and transfer of charge from donor to acceptor [1,2]. Charge transfer complexes play a vital role in many biological fields, such as DNA-binding, antibacterial, antifungal, insecticides as well as take part a central role in the field of drug receptor binding mechanism due to the presence of aromatic electron donors and electron acceptors containing nitrogen, oxygen or sulfur atoms3456789. A great deal of interest has been focused on charge transfer complexes in recent years, because of their great extent application in the field of physiochemical and biochemistry. ...
Studies concentration on hydrogen-bonded charge-transfer complex formed on the reaction between basic 2,3-dimethylquinoxaline with p-toluenesulfonic acid. The crystal was characterized by IR, NMR, thermal and elemental analysis. The crystal structure was deduced by single crystal X-ray diffraction studies which indicated that cation and anion are linked through strong N(+)-H---O(-) type of hydrogen bond. The hydrogen bonded charge transfer crystal was screened for its pharmacology, such as Calf thymus DNA binding/cleavage, antioxidant properties. The results indicated that the compound could interact with DNA through intercalation and should have weak to moderate capacity of scavenging with DPPH. The high thermal stability is due to the molecular frame work through H-bonding interaction. The microbial activities of synthesised compound were examined against various bacteria and fungi species.
... The decision was based on the following considerations. First, the process of molecular simplification [18] was utilized whereby one of the aryl rings and a carbonyl function in the Nacyl groups of 3 were excised. Second, the aryl substituents in 4a Á/f,i were made identical to those found in 3aÁ/d, fÁ/h so that comparisons of the potencies of these compounds could be made. ...
... Dentre estes parâmetros, as energias do HOMO e do LUMO estão correlacionadas às habilidades de doador e aceptor de elétron, respectivamente. Uma maior energia do HOMO está correlacionada com uma maior probabilidade de doar elétrons, enquanto que uma menor energia do LUMO está relacionada a uma maior facilidade em aceitar elétrons 31,32 . ...
... Serious toxicity has occurred primarily when CAP was given in high doses to patients with collagen vascular disease or renal insufficiency. Minor toxic effects which are seen include altered sense of taste, allergic skin rashes, and drug fever [12,13]. CAP has been determined by several methods such as gas chromatography-mass spectrometry (GC-MS) [14], high performance liquid chromatography (HPLC) [15], photometry [16], fluorometry [17], chemiluminometry [18], flow injection and sequential injection analysis [19]. ...
a b s t r a c t A novel modified carbon paste electrode (CPE) based on a new synthesized compound of (E)-3-((2-(2,4-dinitrophenyl)hydrazono)methyl)benzene-1,2-diol (DHB) and carbon nanotubes (CNTs) was prepared. At first the redox properties of the modified electrode was studied by cyclic voltammetry (CV). Then the modified electrode was used as an electrochemical sensor for oxidation of captopril (CAP). Under the optimum pH of 7.0, the overpotential of CAP oxidation decreases about 500 mV at modified electrode than unmodified CPE. Differential pulse voltammetry (DPV) of CAP at the electrochemical sensor exhib-ited two linear dynamic ranges with a detection limit (3r) of 70 nM. Also DPV was used for selective and simultaneous determination of CAP, acetaminophen (AC) and tryptophan (Trp) by the electrochemical sensor. The proposed electrochemical sensor was used for determination of these substances in real sample. Ó 2012 Elsevier B.V. All rights reserved.
... Sulfonamides are drugs extensively used for the treatment of several infections caused by gram-positive and gram-negative microorganisms, some fungi, and certain protozoa. Although the advent of the antibiotics has diminished the clinical use of sulfonamides, these drugs still occupy an important place in the therapeutic resources of physicians and veter- inarians [3,4]. Several thermodynamic works have been published about the enthalpic and entropic contributions to the Gibbs energy of solution of some sulfonamides in binary mixtures conformed by ethanol or propylene glycol and water [5][6][7][8][9]. ...
The preferential solvation parameters of sulfadiazine, sulfamerazine and sulfamethazine in ethanol + water binary mixtures were derived from their thermodynamic properties by means of the inverse Kirkwood–Buff integrals (IKBI) method. From solvent effect studies, it is found that these sulfonamides are sensitive to solvation effects, so the preferential solvation parameter by ethanol δxE,S, is negative in water-rich and ethanol-rich mixtures but positive in compositions from 0.24 to 0.54–0.58 in mole fraction of ethanol according to the sulfonamide. It is conjecturable that in water-rich mixtures the hydrophobic hydration around aromatic rings and/or methyl groups plays a relevant role in the solvation. The more solvation by ethanol in mixtures of similar co-solvent compositions could be due mainly to polarity effects. Finally, the preference of these drugs for water in ethanol-rich mixtures could be explained in terms of the bigger acidic behavior of water interacting with hydrogen-acceptor groups in the sulfonamides.
Nature is reach source of biomolecules. Nowadays, researchers are trying to find potency of natural products against various diseases. All most all of the diseases had been cured by the use of plants before research of synthetic drugs. Most synthetic drugs show similar molecular structures with natural products. In present days also variety of diseases are employing the use of plants extract as herbal medicine, because of no side effects. Considering all these things in mind, it was decided to do proximate analysis of leaves of Gloriosa superba, Family:Liliaceae (Lily family) from Mahan village of Barshitakli Tahesil in Akola District in laboratory. ________________________________________________________________________________
We report in this work, a new method for the determination of captopril by differential pulse voltammetry using a glassy carbon electrode modified with a copper metal-organic framework (H-Kust-1 or Cu3(BTC)2 or Cu-BTC), immobilized on the surface by a copolymer of acrylamide and sodium acrylate. This compound is detected by the formation of a copper(II)-captopril complex that is observed in an oxidation potential at ca. +0.28 V vs. Ag/AgCl. A linear dynamic range is obtained for a captopril concentration of 0.5 μM to 7.0 μM and the voltammetric response is highly reproducible within 3.52 % error. The sensitivity of 9.71±0.37 nA μM⁻¹ and the limit of detection of 0.20±0.01 μM make this methodology highly applicable for practical applications. The determination of captopril in a commercial pharmaceutical sample showed a recovery of 93.3 %.
A number of Indian medicinal plants have been used for thousands of years in the management of cardiovascular diseases such as atherosclerosis, hypertension. Oxidative damage remains as the important factor for the development of cardiovascular diseases. A comparative antioxidant evaluation of three cardio-protective plants pays the better way to fix the proportion of individual plants in the development of new formulation. With this aim, the antioxidant activity of three medicinal plants is evaluated in the in-vitro condition. 70 % ethanolic extract of Nelumbo nucifera (NN), Withania somnifera (WS) and Terminalia arjuna (TA) were tested for their antioxidant activity and IC50 values were determined. To confirm the potent antioxidant plant their phenol, tannin, Vitamin C, Vitamin E and carbohydrate content were also estimated. HPTLC profile of all the three extracts were also taken. The results from the ABTS and nitric oxide radical scavenging assay showed that IC50 value of all the three extracts were similar. Whereas in antilipid peroxidation assay NN has lower IC50 value than other two extracts. Tannin, Vitamin C, Vitamin E and carbohydrate content of TA was found to be high. In NN, Total phenolic content was found to be high. In conclusion, NN is more potent in exhibiting antioxidant activity than the other two extracts. Whereas free radical scavenging activity is exhibited by all the three extracts equally. Along with NN, TA is more potent in phytoconstituents content. Thus increasing the content of NN or TA in the formulation can increase the potency in cardiovascular disorder.
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The inhibitory effect was investigated of 16 different 3-formylchromone
derivatives, the condensation products of 6-Rl-3-formylchromone with 4-aminosalicylic
acid and of the adducts of 6-Rl-3-formylchromone with n-alcohols and
aminosalicylic acids or some other derivatives of aniline, on the photochemical
activity of spinach chloroplasts. The inhibitory activity of the compounds studied
correlated with the lipophilicity of the Rl and R2 (alkoxy) substituents. Using
fluorescence study it was found that the site of action of the studied effectors is
photosystem (PS) 2. By EPR spectroscopy it was confirmed that the studied
effectors interact with the intermediatesZ+lY+ which are situated in D I and D 2
proteins on the donor side of PS 2 which is reflected in a partial decrease in the
photosynthetic electron flow through PS 2 to PS 1. It was found that the core of
PS 2 is not damaged.
It has long been the dream of the medicinal chemist to design drugs that have a specific pharmacological action.1, 2 In the pharmaceutical and agrochemical industries, many thousands of compounds are synthesized and each is tested experimentally to see whether it has the desired properties. Just one in 5000 potential drugs will eventually prove to be a success, and it typically takes ten years to bring a new product to market at an average cost of £120–150m.3 The drug discovery process has thus relied on the skill of the synthetic organic chemist to provide an unlimited supply of novel compounds for screening. The challenge of medicinal chemistry has become not HOW to make a compound, but WHAT to make.’4 There would be obvious benefits, both intellectually and commercially, if the effects of a given molecule could be predicted and molecules could be designed to fulfil a specific purpose.
A novel mononuclear Mn(II), Zn(II) and Cd(II) complexes of pantoprazole (PA) was synthesized and characterized by elemental analysis, molar conductivity, magnetic susceptibility measurements, IR, UV-visible spectral studies, and thermal analysis. The electronic spectra along with magnetic data suggest octahedral geometry for Mn(II), Zn(II) and Cd(II) complexes. PA acts as an anionic bi-dentate ligand being coordinated by (S=O) oxygen and benzimdazolyl nitrogen atoms. The interaction of the complexes with calf thymus DNA (CT-DNA) was monitored by blue shift and hyperchromism in the UV-vis spectra. The observed intrinsic binding constants together with structural analysis of the complexes indicate the groove binding. The binding constants were determined at 303°K, 308°K and 313°K. A thermodynamic analysis showed that the reaction is spontaneous with ΔG being negative. The enthalpy ΔH and the entropy ΔS of reactions were all determined.
Two sensitive and selective analytical methods were developed for simultaneous determination of aminoacridine hydrochloride
and lidocaine hydrochloride in bulk powder and pharmaceutical formulation. Method A was based on HPLC separation of the cited
drugs with determination of the toxic lidocaine-related impurity 2,6-dimethylaniline. The separation was achieved using reversed-phase
column C18, 250 × 4.6 mm, 5 µm particle size and mobile phase consisting of 0.05 M disodium hydrogen phosphate dihydrate (pH
6.0 ± 0.2 adjusted with phosphoric acid) and acetonitrile (55 : 45, v/v). Quantitation was achieved with UV detection at 240
nm. Linear calibration curve was in the range of 1.00–10.00, 13.20–132.00 and 1.32–13.20 µg mL−1 for aminoacridine hydrochloride, lidocaine hydrochloride and 2,6-dimethylaniline, respectively. Method B was based on TLC
separation of the cited drugs followed by densitometric measurement at 365 nm on the fluorescent mode for aminoacridine hydrochloride
and 220 nm on the absorption mode for lidocaine hydrochloride. The separation was carried out using ethyl acetate–methanol–acetic
acid (65 : 30 : 5 by volume) as a developing system. The calibration curve was in the range of 25.00–250.00 ng spot−1 and 0.99–9.90 µg spot−1 for aminoacridine hydrochloride and lidocaine hydrochloride, respectively. The results obtained were statistically analyzed
and compared with those obtained by applying the manufacturer's method.
The amoxicillin 500 mg formulations were developed by direct compression using a 23 factorial design. Eight different formulations were carried out and they were analyzed considering three levels: the type of microcrystalline cellulose (Avicel® PH-102 or Avicel® PH-200), the presence or absence of spray-dried lactose, and the presence or absence of the superdisintegrant agent, croscarmellose sodium. Average weight, thickness and diameter, hardness, friability, amoxicillin concentration (iodometric assay), disintegration time, and dissolution profile were the parameters used for the tablets evaluation. Considering all evaluated parameters, a suitable amoxicillin 500 mg tablet formulation should present the microcrystalline cellulose type Avicel® PH-102 and the superdisintegrant agent, croscarmellose sodium (Ac-disol® SD-711), in its composition.
Discover the inventions that have made our world what it is today. A great invention opens the door to a new era in human history. The stone axe, for example, invented some 2 million years ago in East Africa, enabled us to enter the human path of endless improvements through inventions. The taming of fire enabled us to cook food as well as leave the warmth of Africa and move to the frigid lands of the North. From the stone axe to the computer and the Internet, this book provides a fascinating tour of the most important inventions and inventors throughout history. You'll discover the landmark achievements and the men and women that made the world what it is today. Great Inventions That Changed the World is written by Professor James Wei, a renowned educator and engineer who holds several patents for his own inventions. Following an introductory chapter examining the role of inventors and inventions in fueling innovation and global advancement, the book is organized to show how inventions are spurred by human needs and desires, including: • Work • Food, clothing, and housing • Health and reproduction • Security. As you progress through the book, you'll not only learn about inventions and inventors, but also the impact they have had on our lives and the society and environment in which we live today. Inventions solve problems, but as this book so expertly demonstrates, they can also directly or indirectly create new problems as well, from pollution to global warming to bioterrorism. By enabling us to understand the impact of inventions throughout history, this book can help guide the next generation of citizens, decision makers, and inventors.
Nicotinamide, an important vitamin in our bodies, was found to form beautifully colored charge-transfer complexes with p-chloranil, chloranilic acid and 2,3-dichloro-4,5-dicyano benzoquinone in acetonitrile with absorption maxima at 474.5, 519.0 and 614.0 nm, respectively. The compositions of the complexes were determined to be 1:1 from Job’s method of continuous variation. The measured FTIR spectra of the solid complexes formed between nicotinamide and the acceptors and the corresponding individual constituents showed considerable shifts in absorption peaks, changes in intensities of the peaks and formation of the new bands upon complexation. The thermodynamic association constants K
DA and other thermodynamic parameters (ΔG°, ΔH° and ΔS°) of the complexes, determined spectrophotometrically taking D (donor) and (acceptor) A in varying ratios (2:8–8:2) and also in equimolar ratios, showed the complex formation to be spontaneous. The experimental hν
CT and the theoretical hν
CT values (calculated using density function theory) of the charge-transfer complexes are compared. The hν
CT (experimental) values of the transition energies of the complexes in acetonitrile differ from hν
CT (theoretical) values in the gaseous state. The \( I_{\text{D}}^{\text{V}} \) value of nicotinamide was calculated. A comparative study of the energetics of the partial electrovalent charge-transfer complexes with the organic dative ions D+ and A− (in the excited state) and true electrovalent compounds between M+ and X− is presented.
The discovery of drugs depends on a number of interdependent factors, including insight, serendipity, and persistence. A common characteristic of the successful program is a clearly delineated strategy based on quantitative pharmacological assays. The particular problem chosen often will influence this strategy and dictate the type of approach; that is, either a rational or an empirical one. Depending on this selection, the synthetic targets then will either be derived from drug design concepts for the former or developed around systematic variation of a lead compound for the latter.
Conformational isomerism, present in almost all commercially available pharmaceuticals as well as compounds under clinical and pre-clinical evaluation, plays a key role in the activity of drug molecules. An understanding of the concepts discussed above - preferred conformation, active conformation, advantages and disadvantages of conformational restriction, and strategies to develop conformationally restricted analogs - is crucial to the chemical design of new compounds. Additional examples and further discussion of these concepts can be found in the references included within.
The preferential solvation parameters, that is, the difference between the local and bulk mole fractions of the solvents in solutions of some structurally related sulfonamides in 1,4-dioxane + water binary mixtures are derived from their thermodynamic properties by means of the inverse Kirkwood-Buff integrals method. From solvent effect studies, it was found that all the sulfonamides considered were very sensitive to solvation effects, so the preferential solvation parameter, deltaxD,S, was negative in water-rich and 1,4-dioxane-rich mixtures but positive in intermediate co-solvent compositions. It may be possible that in water-rich mixtures the hydrophobic hydration around the non-polar groups plays a relevant role in the solvation. The greater solvation by 1,4-dioxane in mixtures of similar co-solvent compositions could be due mainly to polarity effects. Finally, the preference of these drugs for water in 1,4-dioxane-rich mixtures could be explained in terms of the acidic behavior of water interacting with the hydrogen-acceptor groups in the sulfonamides.
All natural products can term bioactive molecules, as every diverse molecule possesses one kind or multiple kinds of biological oblique pharmacological activities. U.S. and European countries are now realizing the significance of the Nature's green gift and so they are making patients of herbal drugs. The significance and applications of phytopharmaceutical (also called as herbal medicines) are due to efficiency of curing almost all diseases in human beings. Since ages passed over traditional systems of medicine have depended on natural products derived from plant sources. Hence taking these entire things into consideration it creates sufficient interest to carry out proximate analysis of leaves of Ricinus communis from Chandur (Rly) Amravati. The primitive peoples of antiquity have been using Ricinus communis leaves due to its curative properties. These practioner knew medicinal value of Ricinus communis. These used for remedy in various diseases, but they do not know the exact scientific knowledge of it. Therefore the present objective of study was taken to explore possible mechanism of medicinal activity of Ricinus Communis. INTRODUCTION In Maharashtra State of India, Amravati district is located. This area is very rich of flora and fauna having various types' medicinal plants as it is present in the ranges of Satpuda Mauntain. In past decades there are many medicinal plants, which have been used in traditional medicines for their curative property without any scientific support and pharmacological evidences. As various parts of Ricinus communis. are used for the treatments of various diseases so this plant has it's own identity in medicinal, pharmaceutical and chemical sciences
Purpose - Prodrug design is a strategy that can be used to adjust physicochemical properties of drugs in order to overcome pharmacokinetic problems, such as poor oral bioavailability. However, Lipinski´s and Veber´s rules predict whether compounds will have absorption problems even before the design of prodrugs. In this context, our goal was to evaluate the molecular properties which most influenced the absorption process of prodrugs compared to its precursor through exploratory data analysis approach.
A variety of prodrugs and respective precursors were randomly selected and classified by its percentage of human intestinal absorption. Subsequently, different molecular properties were calculated and hierarchical cluster analysis (HCA) and principal components analysis (PCA) were carried out.
According to the findings, antiviral, anti-hypertensive, and antibiotic prodrugs exhibited higher absorption levels than their respective precursors. Also, some relevant descriptors (molecular weight, MW, routable bonds, rot_bonds, hydrogen bond acceptors, HBA_count and polar surface area, PSA), which are included in Lipinski´s and Veber´s rules, influenced the separation process between prodrugs and drugs. Furthermore, other molecular properties, such as polarizability (α) and molar refractivity (MR), were pointed out.
Lipinski´s and Veber´s rules proved to be important to design an orally administered drug but other descriptors should be considered by medicinal chemists in the prodrug designing process.
Bioisosteres are atoms or group of molecules that fit the broadest definition for isosteres. They have chemical and physical similarities thus producing broadly similar biological properties. Many heterocycles, when appropriately substituted exhibits bioisosterism. Bioisosterism represents an approach used by the medicinal chemist for the rational modification of lead compounds into safer and more clinically effective agents. It has significant value in drug design and lead optimization process as it may enhance the desired biological or physical properties of a compound, reduce toxicity and also alter the metabolism of the lead. Bioisosteric replacement is not simple replacement with another isostere but they are firstly analyzed by structural, solubility and electronic parameters to obtain molecules having similar biological activity. Few of the popular examples of the successful use of bioisosteres have been included. The objective of this review is to provide an overview of bioisosteric replacements which can be used for advance drug development.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
The synthesis, as well as spectroscopic and biological studies of a novel class of [3-(4-substitutedphenylamino)-8-azabicyclo [3.2.1] oct-8yl]-phenyl-methanone derivatives are described. All the synthesized compounds were characterized by elemental analysis FTIR, -NMR, NMR, and Mass spectral data. All the synthesized compounds were exhibit in vitro antibacterial activity.
The preferential solvation parameters, that is, the difference between the local and bulk mole fractions of the solvents in solutions of some structurally related sulfonamides in 1,4-dioxane + water binary mixtures are derived from their thermodynamic properties by means of the inverse Kirkwood-Buff integrals method. From solvent effect studies, it was found that all the sulfonamides considered were very sensitive to solvation effects, so the preferential solvation parameter, δxD,S, was negative in water-rich and 1,4-dioxane-rich mixtures but positive in intermediate co- solvent compositions. It may be possible that in water-rich mixtures the hydrophobic hydration around the non-polar groups plays a relevant role in the solvation. The greater solvation by 1,4-dioxane in mixtures of similar co-solvent compositions could be due mainly to polarity effects. Finally, the preference of these drugs for water in 1,4-dioxane- rich mixtures could be explained in terms of the acidic behavior of water interacting with the hydrogen-acceptor groups in the sulfonamides.
The Sociedade Brasileira de Química is commemorating its 25th anniversary, and this paper is intended to draw an overview of the Brazilian Medicinal Chemistry over all these years. In 1977 Brazil had almost no activities at all in the field, albeit many efforts were already on the way for encouraging Brazilian Scientists to enter the area. Among many different endeavours to help medicinal chemists to fulfil their proposals and the establishment of an on-going research with the help of networks, the Sociedade Brasileira de Química created, in 1991, its own Division on Structure and Activity Relationship, which became the Division of Medicinal Chemistry, in 1997.
Currently available anti-HIV drugs can be classified into three categories: nucleoside analogue reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs) and protease inhibitors (PIs). In addition to the reverse transcriptase (RT) and protease reaction, various other events in the HIV replicative cycle can be considered as potential targets for chemotherapeutic intervention: (1) viral adsorption, through binding to the viral envelope glycoprotein gp120; (2) viral entry, through blockage of the viral coreceptors CXCR4 and CCR5; (3) virus-cell fusion, through binding to the viral envelope glycoprotein gp 41; (4) viral assembly and disassembly through NCp7 zinc finger-targeted agents; (5) proviral DNA integration, through integrase inhibitors and (6) viral mRNA transcription, through inhibitors of the transcription (transactivation) process. Also, various new NRTIs, NNRTIs and PIs have been developed, possessing different improved characteristics.
The preferential solvation parameters, which represent differences between the local and bulk mole fractions of the solvents near to the solute, in solutions of some sulfonamides in propylene glycol + water binary mixtures are derived from their thermodynamic properties by means of the inverse Kirkwood−Buff integrals (IKBI) and the Quasi-Lattice Quasi-Chemical (QLQC) method. From solvent effect studies, it is found that sulfonamides are sensitive to solvation effects; the preferential solvation parameter, δx
PG,S, is negative in water-rich mixtures but positive in compositions from 0.20 to 1.00 in mole fraction of propylene glycol according to IKBI method and positive in all co-solvent compositions if the QLQC method is considered. It is conjecturable that in water-rich mixtures, hydrophobic hydration around the aromatic ring and/or other non-polar groups plays a relevant role in the solvation. The greater solvation by propylene glycol mixtures of similar solvent compositions and in co-solvent-rich mixtures could be due mainly to polarity effects and acidic behavior of the sulfonamides, in contrast to the more basic solvent propylene glycol.
ResearchGate has not been able to resolve any references for this publication.