Dihydropyrimidines 4a-r have been synthesized by base catalysed condensation of beta-aroylpropanoic acid, guanidine nitrate and aromatic aldehyde. Structures of the new compounds were established on the basis of 1H NMR and IR spectral data. Anti-inflammatory activity in vivo was evaluated and compared with standard drug diclofenac sodium.

Thirteen 5-hetarylaminopyrazoles were synthesized in 62-93% yield through the arylation of 1-isopropyl- and 1-phenyl-5-aminopyrazoles with electrophilic hetarylhalides under optimized conditions. Condensation of 5-hetarylaminopyrazoles with carbonyl compounds facilitated by AcOH or Me(3)SiCl furnished 23 pyrazolo[3,4-d]dihydropyrimidines in 69-86% yield. The target compounds were isolated throu...

Dihydropyrimidines are associated with wide range of biological activities. Keeping this in view 6-phenyl-4substituted phenyl-2-thioxo-1,2,3,4-tetrahydropyrimidin-5-carboxylic acid ethyl ester were prepared under microwave irradiations. These were converted to S-alky/S-benzyl-1,4dihydropyrimidines for synthesizing biologically active molecules with improved activity. These are regarded as aza-a...

An enantioselective Biginelli reaction has been developed by using a bifunctional primary amine-thiourea-TfOH (BPAT·TfOH) as a chiral phase-transfer catalyst and t-BuNH(2)·TFA as an additive in saturated brine at room temperature. The corresponding dihydropyrimidines were obtained in moderate-to-good yields with up to 99% ee under mild conditions. A plausible transition state has been proposed ...

A series of 2-methylthio-1,4-dihydropyrimidine derivatives (II) were synthesized in good yields by alkylation of 1,2,3,4-tetrahydropyrimidines (I) with methyl iodide in the presence of pyridine. Their structures were confirmed by elemental analysis, IR and 1H NMR spectra. The compounds were tested for analgesic activity by acetic acid induced writhing method. Compounds IIh, IIe, IIk and IIl sho...

The mechansim of the three-component Biginelli dihydropyrimidine synthesis was reinvestigated using (1)H and (13)C NMR spectroscopy. Condensation of benzaldehyde, ethyl acetoacetate, and urea (or N-methylurea) in CD(3)OH according to the procedure described by Biginelli produced the expected 6-methyl-2-oxo-4-phenyl-1,2,3,4-tetrahydropyrimidine-5-carboxylates. According to NMR measurements, ther...

A series of 2-methylthio-1,4-dihydropyrimidine derivatives (II) were synthesized in good yields by alkylation of 1,2,3,4-tetrahydropyrimidines (I) with methyl iodide in the presence of pyridine. Their structures were confirmed by elemental analysis, IR and 1H NMR spectra. The compounds were tested for analgesic activity by acetic acid induced writhing method. Compounds IIh, IIe, IIk and IIl sho...

a series of 2-methylthio-1,4-dihydropyrimidine derivatives (ii) were synthesized in good yields by alkylation of 1,2,3,4-tetrahydropyrimidines (i) with methyl iodide in the presence of pyridine. their structures were confirmed by elemental analysis, ir and 1h nmr spectra. the compounds were tested for analgesic activity by acetic acid induced writhing method. compounds iih, iie, iik and iil sho...