NISCAIR Online Periodicals Repository Collection: IJC-B Vol.50B(10) [October 2011]

Heterogeneous catalyst: Silica sulfuric acid catalyzed synthesis of 9, 10-dihydro-12-aryl-8H-benzo[]xanthen-11(12H)-one derivatives under solvent-free conditions

Wed, 28 Sep 2011 22:58:59 GMT

Title: Heterogeneous catalyst: Silica sulfuric acid catalyzed synthesis of 9, 10-dihydro-12-aryl-8H-benzo[]xanthen-11(12H)-one derivatives under solvent-free conditions

Authors: Nazeruddin, G M; Pandharpatte, Mahesh S; Mulani, Khudbudin B

Abstract: Silica sulfuric acid (SSA) as an efficient and reusable heterogeneous catalyst has been used for the preparation of 9,10-dihydro-12-aryl-8H-benzo[]xanthen-11(12H)-one derivatives from the three-component condensation reaction of b-naphthol, cyclic 1,3 dicarbonyl compounds and aromatic aldehydes under solvent-free conditions in good to excellent yields and short reaction times.

Page(s): 1532-1537

Synthesis of some 3-(5-chloro-1,3-diaryl-1H-pyrazol-4-yl)-1-arylprop-2-en-1-ones and 1,5-bis(5-chloro-1,3-diaryl-1H-pyrazol-4-yl)pent-1,4-diene-3-ones and their antimicrobial activity

Wed, 28 Sep 2011 22:58:59 GMT

Title: Synthesis of some 3-(5-chloro-1,3-diaryl-1H-pyrazol-4-yl)-1-arylprop-2-en-1-ones and 1,5-bis(5-chloro-1,3-diaryl-1H-pyrazol-4-yl)pent-1,4-diene-3-ones and their antimicrobial activity

Authors: Rani, Archna; Jain, Sapna; Dureja, Prem; Kumar, Rita; Kumar, Anil

Abstract: New 3-(5-chloro-1,3-diaryl-1H-pyrazol-4-yl)-1-arylprop-2-en-1-ones (4a-n) and 1,5-bis(5-chloro-1,3-diaryl-1H-pyrazol-4-yl)pent-1,4-diene-3-ones (4o-r) have been synthesized by using aryl-5-chloro-4-formyl-1,2-pyrazoles (2a-d) as key intermediate, prepared by Vilsmeir-Haack reaction of pyrazolones. The compounds have been screened against multihost plant pathogenic fungi Macrophomina phaseolina and Sclerotium rolfsii and human pathogenic bacteria MTCCB 96 Staphylococcus aureus, MTCCB 1610 Escherichia coli, clinical isolate Citrobacter Sp. and Enterococcus faecium. Some compounds have shown promising activity against these microbes. Regression analysis has also been done for relationship between antifungal activity and concentration of compounds.

Page(s): 1524-1531

Microwave assisted one-pot synthesis of pyrazine derivatives of pentacyclic triterpenoids and their biological activity

Wed, 28 Sep 2011 22:58:59 GMT

Title: Microwave assisted one-pot synthesis of pyrazine derivatives of pentacyclic triterpenoids and their biological activity

Authors: Ghosh, Pranab; Rasul, Md. Golam; Chakraborty, Madhumita; Mandal, Amitava; Saha, Aniruddha

Abstract: One-pot synthesis of 1,4-pyrazine derivative of pentacyclic triterpene has been carried out under microwave irradiation and the antimicrobial potential associated with them has been evaluated. The structures of the compounds have been confirmed by spectral data (IR, NMR). Compounds 1b, 2b and 3b have been reported for the first time.

Page(s): 1519-1523

Preparation of nitrones and studies of their intramolecular 1,3-dipolar cycloaddition reactions

Wed, 28 Sep 2011 22:58:59 GMT

Title: Preparation of nitrones and studies of their intramolecular 1,3-dipolar cycloaddition reactions

Authors: Roy, Brindaban; De, Rajendra Narayan

Abstract: Nitrones are prepared from different 2-allyloxy-1-benzaldehydes and intramolecular 1,3-dipolar cycloaddition reaction of these nitrones have been studied in different solvents at their boiling points.

Page(s): 1513-1518