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An improved method for the synthesis of some new dihydropyrimidines from aromatic aldehydes, 1,3-dicarbonyl compounds, and thiourea with significant enhancement in reaction rates, short reaction time (4–6 h), good to excellent yields (70–93%), and ambient temperature using molecular iodine as catalyst is described. The biological evaluation revealed that the newly synthesized compounds and exhibited good antimicrobial activity and moderate antimycobacterial activity against Mycobacterium tuberculosis H37RV.

Heterosubstituted chalcones and oxopyrimidines were synthesized by the reaction of 2-(4-Chlorophenyl)imidazo[1,2-a]pyridine-3-carbaldehyde 1 and different aryl acetophenone in the presence of catalytic amount of 40% alkali to give (2E)-3-(2-(4-chlorophenyl)imidazo[1,2-a]pyridin-3-yl)-1-arylprop-2-en-1-ones 2a–l. Compounds 2a–l on reaction with urea in the presence of basic catalyst such as KOH to give 6-(2-(4-chlorophenyl)imidazo[1,2-a]pyridin-3-yl)-4-aryl pyrimidin-2(1H)-ones 3a–l. Their IR, 1H-NMR, MASS spectral data, and elemental analysis were in accord with assigned structure. All the newly synthesized compounds were screened for their antimicrobial activity. J. Heterocyclic Chem., (2012).

4-(2-hydroxyphenylamino)-pent-3-en-2-one (HPAP) was synthesized and single crystals were grown by the solution growth technique using methanol as a solvent. The crystals having orthorhombic symmetry were characterized by single crystal XRD, FTIR spectroscopy, NMR spectroscopy, TGA, DSC and dielectric studies. Very less variation in the value of dielectric constant is found for different frequencies of applied field. The crystals were exhibiting positive photoconductivity and poor NLO responses. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Background: Bronchogenic carcinoma is the most common cancer in Nepal. There is no information available about the incidence and clinicopathological features of bronchogenic carcinoma from Nepal. We aimed to study the clinicopathological features of primary bronchogenic carcinoma treated in a tertiary care hospital. Methods: A retrospective case-series analysis of 136 cases of primary bronchogenic carcinoma treated between September 2001 and August 2005 in a tertiary care hospital of western Nepal was performed. Results: The median age of the male and female patients was 67 (interquartile range 60, 71.75) and 66 (interquartile range 60, 70) years, respectively. The maximum number of patients was in the 60–69 year age group. One-hundred and thirteen (83.1%) of these patients were smokers. Among the male patients, 83.3% (60/72) were smokers and females 82.8% (53/64) were smokers. The male to female ratio of the patients was 1.1: 1. The most common histological type was squamous-cell carcinoma (51.5%), followed by small-cell carcinoma (17.6%) and adenocarcinoma (8.1%). Ninety-eight (72.1%) patients were diagnosed in late stages of the disease (IIIb and IV). Conclusion: The clinicopathological features are in accordance with reports from other studies. The results of the present study indicate that bronchogenic carcinoma has a higher average age incidence, higher proportion of female patients and higher proportion of diagnosis of the disease in late stages. The higher rate of bronchogenic carcinoma among females indicates scope for further research into risk factors. Intervention measures for prevention and early diagnosis of bronchogenic carcinoma are to be undertaken.

The formation of dihydropyrimidines (IV) and (VII) from dicarbonyl compounds, aromatic aldehydes, and thiourea derivatives occurs with significant enhancement with regard to reaction rates, reaction time, and yield by using molecular iodine as the catalyst.

Heterosubstituted chalcones and oxopyrimidines were synthesized by the reaction of 2-(4-Chlorophenyl)imidazo[1,2-a]pyridine-3-carbaldehyde 1 and different aryl acetophenone in the presence of catalytic amount of 40% alkali to give (2E)-3-(2-(4-chlorophenyl)imidazo[1,2-a]pyridin-3-yl)-1-arylprop-2-en-1-ones 2a–l. Compounds 2a–l on reaction with urea in the presence of basic catalyst such as KOH to give 6-(2-(4-chlorophenyl)imidazo[1,2-a]pyridin-3-yl)-4-aryl pyrimidin-2(1H)-ones 3a–l. Their IR, 1H-NMR, MASS spectral data, and elemental analysis were in accord with assigned structure. All the newly synthesized compounds were screened for their antimicrobial activity. J. Heterocyclic Chem., (2012).

The series of compounds 6-carbethoxy-5-aryl-3-(3,5-dibromo-4-methoxy phenyl)-2-cyclohexenones 2a-j are obtained from the (2E)-1-(3,5-dibromo-4-methoxyphenyl)-3-aryl-prop-2-en-1-ones 1a-j by Michael addition of ethyl acetoacetate, followed by internal Claisen condensation. Reaction of 2a-j with hydrazine hydrate afforded the corresponding 6-(3,5-dibromo-4-methoxyphenyl)-4-aryl-2,3a,4,5-tetrahydro-3H-indazol-3-ones 3a-j. The constitution of all the synthesized compounds have been established by elemental analyses, IR, 1 H NMR and mass spectral data. All the compounds have been screened for their antimicrobial activities and compounds 2a-j have been tested for antitubercular activity.

2-Amino-3-cyano-6-(3,5-dibromo-4-methoxyphenyl)-4-aryl-pyridines 2a-i arc synthesized by the reaction of compounds (2E)-3-(3,5-dibromo-4-methoxyphenyl)-1-arylprop-2-en-1-one 1a-i with malononitrile in the presence of ammonium acetate. Condensation of compounds 1a-i with malononitrile in pyridine has yielded 2-amino-3-cyano-6-(3,5-dibromo-4-methoxyphenyl)-4-arylpyrans 3a-i. The constitution of all the synthesized compounds have been cstablished by elemental analyses, IR, 1 H NMR, and mass spectral data. All the compounds arc screened for their antitubercular and antimicrobial activities.

2-(2,4-Dichlorophenyl)imidazo[1,2-a]pyridine-3-carbaldehyde (1) was prepared from 2-aminopyridine through multi-step reaction. Compound 1 reacts with different aryl ketones in the presence of catalytic amount of 40% KOH to give (2E)-3-[2-(2,4-dichlorophenyl)imidazo[1,2-a]pyridin-3-yl]-1-arylprop-2-en-l-ones (2a-j), which on cyclization with urea and thiourea in the presence of basic catalyst like KOH afforded 6-[2-(2,4-dichlorophenyl)imidazo[1,2-a]pyridine-3-yl]-4-aryl-pyrimidin-2(1H)-ones (3a-j) and 6-[2-(2,4-dichlorophenyl)imidazo[1,2-a]pyridine-3-yl]-4-aryl-pyrimidin-2(1H)-thiones (4a-j). The antimicrobial evaluations have been performed for their antibacterial activity and antifungal activities.

A wide range of biological activities are associated with 1,4-dihydropyridines Individually or in combination. The synthesis of N-aryl-2,6-dimethyl-3,5-dicarbmethoxy-4-[5'-(m-chloro-p-flourophenyl)-2'-furyl]-1,4-dihydropyridines (6a-J) and N-aryl-2,6-dimethyl-3,5-dicarbmethoxy-4-[5'-(m-chloro-p-flourophenyl)-2'-furyl]-1,4-dihydropyrldines (7a-j) was under-taken with hope that they may be biologically active molecules with improved activity, less toxicity and undesirable side effects. The newly synthesized compounds were characterized on the basis of elemental analysis, IR, 1 H NMR and mass spectral data. All newly synthesized compounds were tested for their antitubercular activity against Mycobacterium tuberculosis H 37 RV ATCC 27294, antibacterial activity against different Gram +ve and Gram -ve bacteria and antifungal activity.

Cyclocondensation of hydrazine hydrate with (2E)-1-(3,5-dibromo-4-methoxyphenyl)-3-aryl-prop-2-en-l-onts (la-j) in glacial acetic acid afford corresponding l-acetyl-3-(3,5-dibromo-4-methoxyphenyl)-5-aryl-4,5-dihydro-1H-pyrazoles (2a-j). While the compounds la-j on reaction with hydroxylamine hydrochloride in presence of acetic acid and sodium acetate to give 3-(3,5-dibromo-4-methoxyphenyl)-5-aryl-isoxazoles (3a-j). All the compounds were tested against different microbes for their antimicrobial activity and compounds 2a-j were tested for antitubercular activity.

Substituted 4-thiazolidinones 3a-1 have been prepared by the condensation of 2-(substituted-benzalhydrazinocarbonyl)-3,5-dichlorobenzo(b)thiophene 2a-1 with thioglycolic acid. The synthesis of 2-azetidinones 4a-1 has beenundertaken by the reaction of 2a-1 with chloroacetyl chloride in the presence of triethyl amine. The structures of the compounds synthesised are assigned on the basis of elemental analysis, IR and 1 H NMR spectral studies.