Synthesis, antiviral, antituberculostic, and antibacterial activities of some novel, 4-(4-substituted phenyl)-6-(4-nitrophenyl)-2-(substituted imino)pyrimidines

A variety of novel 4-(4-substituted phenyl)-6-(4-nitrophenyl)-2-substituted imino) pyrimidines were synthesized by reacting 4-(4-substituted phenyl)-6-(4-nitrophenyl)-2-amino pyrimidines with different substituted aromatic aldehydes, coumarin chloroisatin. The 4-(4-substituted phenyl)-6-(4-nitrophenyl)-2-amino pyrimidines were synthesized by reacting 3-(4'-substituted phenyl)-1-(4-nitrophenyl)-2-propen-1-ones with guanine hydrochloride. 3-(4-Substituted phenyl)-1-(4-nitrophenyl)-2-propen-1-ones were synthesized by reacting 4-nitroacetophenone with different para-substituted aromatic aldehydes. Spectral data (IR, NMR, and mass spectra) confirmed the structures of the synthesized compounds. The synthesized compounds were investigated for their antiviral, antituberculostic, and antibacterial activities. The results of antiviral, antituberculostic, and antibacterial activities indicated that the synthesized compounds exhibited mild to potent activities compared to the respective reference standards.     

Synthesis, antitubercular, antifungal and antibacterial activities of 6-substituted phenyl-2-(3'-substituted phenyl pyridazin-6'-yl)-2,3,4,5-tetrahydropyridazin-3-one

A series of 6-substituted phenyl-2-(3'-substituted phenyl pyridazin-6'-yl)-2,3,4,5-tetrahydropyridazin-3-ones has been synthesized. An appropriate aromatic hydrocarbon reacts with succinic anhydride in presence of AlCl3 to yield beta-aroyl propionic acid. The corresponding acid was cyclized with hydrazine hydrate to give 6-(substituted aryl)-2,3,4,5-tetrahydro-3-pyridazinone, which was heated on steam bath with phosphorus(V) oxychloride to yield 3-chloro 6-substituted phenyl pyridazine. This intermediate after reaction with hydrazine hydrate was converted into 3-hydrazino-6-substituted phenyl pyridazine. The resulting product was converted into 6-substituted phenyl-2-(3'-substituted phenyl pyridazin-6'-yl)-2,3,4,5-tetrahydropyridazin-3-one by reacting with substituted aroyl propionic acid. Spectral data (IR, NMR, mass spectra) confirmed the structures of the synthesized compounds. The synthesized compounds were investigated for their in vitro antitubercular, antifungal and antibacterial activities. The results indicated that the synthesized compounds have mild to potent activities with reference to their appropriate reference standards.     

Synthesis and pharmacological evaluation of some 3-(4-methylphenyl)-2-substituted amino-3H-quinazolin-4-ones as analgesic and anti-inflammatory agents

A variety of 3-(4-methyl phenyl)-2-substituted amino-3H-quinazolin-4-ones were synthesized by reacting the amino group of 2-hydrazino-3-(4-methyl phenyl)-3H-quinazolin-4-one with a variety of aldehydes and ketones. The starting material 2-hydrazino-3-(4-methyl phenyl)-3H-quinazolin-4-one was synthesized from 4-methyl aniline. The title compounds were investigated for analgesic, anti-inflammatory, and ulcerogenic index activities. While the test compounds exhibited significant activity, compounds Al, A2, and A3 showed more potent analgesic activity and the compound A3 showed more potent anti-inflammatory activity when compared to the reference standard diclofenac sodium. Interestingly, the test compounds showed only mild ulcerogenic potential when compared to aspirin.     

Synthesis and antimicrobial activity of 1-(4-hydroxyphenyl)-4-acyl-5-aryl-3-hydroxy-3-pyrrolin-2-ones

The reaction of methyl esters of acylpyruvic acids, 4-aminophenols, and aromatic aldehydes leads to the formation of 1-(4-hydroxyphenyl)-4-acyl-5-aryl-3-hydroxy-3-pyrrolin-2-ones. The proposed structures of the synthesized compounds were confirmed by IR and PMR spectroscopy. The antibacterial activity of some of the newly synthesized compounds was studied.     

Ring substituted 3-phenyl-1-(2-pyrazinyl)-2-propen-1-ones as potential photosynthesis-inhibiting, antifungal and antimycobacterial agents

Four series of ring substituted (E)-3-phenyl-1-(2-pyrazinyl)-2-propen-1-ones were prepared by means of modified Claisen-Schmidt condensation of acetylpyrazines with aromatic aldehydes. The structures were confirmed by elemental analysis, IR, 1H NMR and 13C NMR spectra. The compounds were tested for specific biological properties and some derivatives exhibited photosynthesis-inhibiting, antifungal and antimycobacterial properties. The most pronounced effects were observed with compounds substituted with phenolic groups. Ortho-hydroxyl substituted derivatives were more potent than the corresponding para-hydroxyl substituted analogues.     

Synthesis and biological studies of a novel series of 4-(4-(1H-imidazol-1-yl)phenyl)-6-arylpyrimidin-2-amines

A novel series of eleven 4-(4-(1H-imidazol-1-yl)phenyl)-6-arylpyrimidin-2-amines has been prepared from synthesized 3-[4-(1H-imidazol-1-yl) phenyl]prop-2-en-1-ones and evaluated for phosphodiesterase (PDE) inhibition and antimicrobial activities. N-arylation of imidazole with 4-fluorobenzaldehyde using hexadecyltrimethylammonium bromide as catalyst gave 4-(1H-imidazol-1-yl) benzaldehyde which on treatment with substituted acetophenones yielded corresponding chalcones (1a–1k). Each chalcone on further reaction with guanidine hydrochloride resulted in title compounds (2a–2k). Pyrimidines thus synthesized were subjected to biological studies. Some compounds showed marked activities in PDE inhibition and anti-bacterial and anti-fungal bioassays.     

Anti-inflammatory and analgesic activities of some newly synthesized pyridinedicarbonitrile and benzopyranopyridine derivatives

In continuation of our search for new substituted pyridine based anti-inflammatories, reaction of 1-(2-thienyl or furanyl)-3-(2-hydroxyphenyl)-2-propen-1-ones (1) with malononitrile in alcoholic KOH solution afforded a mixture of 4-alkoxy-2-(2-thienyl or furanyl)-5H-[1]benzopyrano[3,4-c]pyridine-5-ones (2) and 2-alkoxy-4-amino-6- (2-thienyl or furanyl)-3,5-pyridinedicarbonitriles (3). Some of the synthesized compounds were evaluated for their anti-inflammatory and analgesic activities compared to diclofenac potassium as positive control. Detailed synthesis, spectroscopic and toxicity data are reported.     

Synthesis and pharmacological investigation of novel 3-(3-methylphenyl)-2-substituted amino-3H-quinazolin-4-ones as analgesic and anti-inflammatory agents

A variety of novel 3-(3-methylphenyl)-2-substituted amino-3H-quinazolin-4-ones were synthesized by reacting the amino group of 2-hydrazino-3-(3-methylphenyl)-3H-quinazolin-4-one with a variety of aldehydes and ketones. The starting material 2-hydrazino-3-(3-methylphenyl)-3H-quinazolin-4-one was synthesized from 3-methyl aniline. The title compounds were investigated for analgesic, anti-inflammatory and ulcerogenic index activities. Compound 2-(1-ethylpropylidene-hydrazino)-3-(3-methylphenyl)-3H-quinazolin-4-one (AS2) was the most active analgesic agent. Compound 2-(1-methylbutylidene-hydrazino)-3-(3-methylphenyl)-3H-quinazolin-4-one (AS3) was the most active anti-inflammatory agent and was moderately more potent than the reference standard diclofenac sodium. The test compounds showed only mild ulcerogenic potential compared with aspirin.     

Synthesis, structural elucidation and pharmacological properties of some 5-acetyl-3,4-dihydro-6-methyl-4-(substituted phenyl)-2(1H) -pyrimidinones

In this study, the synthesis of some new 5-acetyl-3,4-dihydro-6-methyl-4-(substituted phenyl)-2(1H)-pyrimidinones has been reported. The compounds were prepared by the Biginelli reaction of acetylacetone with aromatic aldehydes and urea. The structures of the compounds were characterized by UV, IR, 1H NMR, 13C NRM, mass spectra and elementary analysis. The calcium antagonistic activity of these compounds was tested in vitro on rat ileum precontracted with 4 x 10(-3) M barium chloride.     

Synthesis and antibacterial activity of some imidazole-5-(4H)one derivatives

In the present study, several substituted oxazolones were synthesized by condensation of benzoylglycine with different aldehydes. From such oxazolones, substituted imidazolones were synthesized by condensation with ethylenediamine, urea and 4-N,N-dimethylaminoaniline. All these synthesized compounds produced significant antibacterial activities. Furthermore, compounds containing -CH(2)CH(2)NH(2), -CONH(2) and -C(6)H(4)-N(CH(3))(2) groups as substitutents on the imidazolones were found to be potent antibacterial agents. Thus, among the twelve compounds, 1-(2-aminoethyl)-2-phen yl-4-(4-(dimethylamino)benzylidene)imidazole-5-(4H)one (4d), 1-carboxamido-2-phenyl-4-(4-(dimethylamino)benzylidene)imidazole-5-(4H)one (4e) and 1-(4-(N,N-dimethylamino)phenyl)-2-phenyl-4-(4-(dimethylamino)benzylidene)imidazole-5-(4H)one (4f) were found to have a significant higher antibacterial activity than the other substituted imidazolones. Compound 4e was the most active one in this series.     

Synthesis and pharmacological evaluation of some 3-(2-methylphenyl)-2-substituted amino-quinazolin-4(3H)-ones as analgesic and antiinflammatory agents

A variety of novel 3-(2-methylphenyl)-2-substituted amino-quinazolin-4(3H)-ones were synthesized by reacting the amino group of 2-hydrazino-3-(2-methylphenyl)-quinazolin-4(3H)-one with a variety of aldehydes and ketones. The starting material 2-hydrazino-3-(2-methylphenyl)-quinazolin-4(3H)-one was synthesized from 2-methyl aniline. The title compounds were investigated for analgesic, anti-inflammatory and ulcerogenic index activities. Among these, the compound 2-(1-ethylpropylidene)-hydrazino-3-(2-methylphenyl)-quinazolin-4(3H)-one emerged as the most active compound for analgesic activity, while the compound 2-(1-methylbutylidene)-hydrazino-3-(2-methylphenyl)-quinazolin-4(3H)-one showed most potent anti-inflamma-tory activity of the series and was moderately more potent in its anti-inflammatory activity when compared to the reference standard diclofenac sodium (CAS 15307-86-5). Interestingly, the test compounds showed only mild ulcerogenic potential when compared to acetylsalicylic acid (CAS No: 50-78-2).     

Synthesis and Pharmacological Evaluation of Azetidin-2-ones and Thiazolidin-4-ones Encompassing Benzothiazole

Various 7-chloro-6-fluoro-2-arylidenylaminobenzo(1,3)thiazole (2a-h) have been synthesized by the condensation of 7-chloro-6-fluoro-2-aminobenzo(1,3)thiazole (1) with different aromatic aldehydes. The Schiff's bases on reaction with acetyl chloride, chloroacetyl chloride and phenyl acetyl chloride yielded 1-(7-chloro-6-fluorobenzothiazol-2-yl)-3,4-substituted-aryl-azetidin-2-ones (3a-x). Similarly, cyclization of Schiff's base with thioglycolic acid furnished 3-(7-chloro-6-fluoro-benzothiazol-2-yl)-2-substituted-arylthiazolidin-4-ones (4a-h). The structures of the newly synthesized compounds have been established on the basis of their spectral data and elemental analysis. Some selected compounds were evaluated for antiinflammatory, analgesic, CNS depressant and skeletal muscle relaxant activity.     

Synthesis, analgesic, anti-inflammatory and antibacterial activities of some novel 2-butyl-3-substituted quinazolin-4-(3H)-ones

A variety of novel 2-butyl-3-substituted quinazolin-4-(3H)-ones have been synthesized by reacting (2-butyl-4-oxo-3H-quinazolin-3-yl)dithiocarbamic acid methyl ester with a variety of amines; the starting material dithiocarbamate was synthesized from anthranilic acid. The title compounds were investigated for analgesic, anti-inflammatory and antibacterial activities. While the test compounds exhibited significant activity, compounds A1, A2, A3 and A4 showed more potent analgesic activity and compound A4 showed more potent anti-inflammatory activity than the reference diclofenac sodium.     

Synthesis, analgesic, anti-inflammatory and antibacterial activities of some novel 2-methylthio-3-substituted quinazolin-4-(3H)-ones

A variety of novel 2-methylthio-3-substituted quinazolin-4-(3H)-ones have been synthesized by reacting (2-methylthio-4-oxo-3H-quinazolin-3-yl)dithiocarbamic acid methyl ester with a variety of amines, the starting material dithiocarbamate was synthesized from methylanthranilate. The title compounds were investigated for analgesic, anti-inflammatory and antibacterial activities. While the test compounds exhibited significant activity, the compounds A1, A2, A3 and A4 shown more potent analgesic activity, and the compound A4 shown more potent anti-inflammatory activity than the reference diclofenac sodium.     

Synthesis and analgesic, anti-inflammatory activities of 3-(3-methoxyphenyl)-2-substituted amino-quinazolin-4(3H)-ones

A variety of novel 3-(3-methoxyphenyl)-2-substituted amino-quinazolin-4(3H)-ones were synthesized by reacting the amino group of 2-hydrazino-3-(3-methoxyphenyl)-quinazolin-4(3H)-one with a variety of aldehydes and ketones. The starting material 2-hydrazino-3-(3-methoxyphenyl)-quinazolin-4(3H)-one was synthesized from 3-methoxy aniline. The title compounds were investigated for analgesic, anti-inflammatory, and ulcerogenic behavior. Among these the compound 2-(1-methyl butylidene-hydrazino)-3-(3-methoxyphenyl)-3H-quinazolin-4-one (AS3) emerged as the most active compound for the analgesic activity, while the compound 2-(1-ethyl propylidene-hydrazino)-3-(3-methyoxyphenyl)-3H-quinazolin-4-one (AS2) showed most potent anti-inflammatory activity of the series and these compounds are moderately more potent when compared to the reference standard diclofenac sodium. Interestingly the test compounds showed only mild ulcerogenic potential when compared to acetylsalicylic acid.     

Synthesis, antimicrobial activity, and molecular modeling of novel 4-(3-(4-benzylpiperazin-1-yl)propoxy)-7-methoxy-3-substituted phenyl-2H-chromen-2-one

A series of novel 4-(3-(4-benzylpiperazin-1-yl)propoxy)-7-methoxy-3-substituted phenyl-2H-chromen-2-one (7a–7j) were synthesized by the reductive amination of 7-methoxy-3-phenyl-4-(3-piperizin-1-yl-propaxy)chromen-2-one (6) with different substituted aromatic aldehydes by using sodium cyanoborohydride in methanol. The newly synthesized compounds were purified and their structures were characterized by IR, ¹H NMR, ¹³C NMR, and mass spectroscopy. The representative analogs were screened for in vitro antimicrobial activity. The compounds exhibited significant antibacterial and antifungal activity as that of standards. The data was further compared with structure-based investigations using docking studies with the crystal structure of oxidoreductase (1XDQ and 3QLS) protein organisms. The estimated score by genetic algorithm was found to have a good correlation with the experimental inhibitory potency of the derivatives.     

Synthesis and antimicrobial activity of some 1-(2,4-dinitrophenyl)-3-(3-nitrophenyl)-5-(4-substituted phenyl)-4-bromo-2-pyrazolines and 1-(2,4-dinitrophenyl)-3-(3-nitrophenyl)-5-(4-substituted phenyl)-2-pyrazolin-4-ones

A series of 1-(2,4-dinitrophenyl)-3-(3-nitrophenyl)-5-(4-substituted phenyl)-2-pyrazolin-4-ones (4a-e) have been synthesized by the oxidation of 1-(2,4-dinitrophenyl)-3-(3-nitrophenyl)-5-(4-substituted phenyl)-4-bromo-2-pyrazolines (3a-e) with dimethylsulfoxide. The structure has been established on the basis of spectral data (IR,1H NMR). The synthesized compounds have been screened in vitro for their possible antimicrobial activity.     

Synthesis and pharmacological investigation of novel 3-(benzyl)-2-substituted amino-3<Emphasis Type="Italic">H</Emphasis>-quinazolin-4-ones as analgesic and anti-inflammatory agents

A variety of novel 3-(benzyl)-2-substituted amino-quinazolin-4(3H)-ones were synthesized by reacting the amino group of 3-benzyl-2-hydrazino quinazolin-4(3H)-one with a variety of aldehydes and ketones. The starting material, 3-benzyl-2-hydrazino quinazolin-4(3H)-one, was synthesized from benzyl amine. The title compounds were investigated for analgesic, anti-inflammatory, and ulcerogenic index activities. The compound 3-benzyl-2-[N’-(1-ethyl-propylidene)-hydrazino]-3H-quinazolin-4-one (AS2) emerged as the most active compound of the series and is moderately more potent in its analgesic and anti-inflammatory activities when compared to the reference standard diclofenac sodium. Interestingly the test compounds showed only mild ulcerogenic potential when compared to aspirin.     

Structure-activity relationship of estrogens: receptor affinity and estrogen antagonist activity of certain (E)- and (Z)-1,2,3-triaryl-2-propen-1-ones

(E)- and (Z)-1,2,3-triphenyl-2-propen-1-ones and some of their phenolic and alkoxy analogues, substituted at the para position in one or more of the aromatic rings, were synthesized and assigned geometry on the basis of their spectroscopic data. The structure-activity relationship of the triarylpropenones was studied from the point of view of their estrogen receptor affinity and estrogen agonist and antagonist activities. (E)- as well as (Z)-propenones were found to compete with estradiol for binding with the mouse uterine cytosol receptors, with phenolic analogues usually more potent than the unsubstituted as well as alkoxypropenones. The (E)-propenones, which have now emerged as a new group of estrogen receptor ligands, were found to differ from Z isomers quite markedly in their binding specificities. The uterotrophic and antiuterotrophic assays in immature mice revealed that while some of the compounds were marginally estrogenic, nearly all the isomeric propenones were antiestrogenic to a varying degree.