NISCAIR Online Periodicals Repository Collection: IJC-B Vol.51B(03) [March 2012]

One-pot, multicomponent synthesis of 4H-pyrano[2,3-c]pyrazoles in water at 25°C

Mon, 27 Feb 2012 22:58:59 GMT

Title: One-pot, multicomponent synthesis of 4H-pyrano[2,3-c]pyrazoles in water at 25°C

Authors: Reddy, M B Madhusudana; Pasha, M A

Abstract: Several pyranopyrazoles are synthesized by an iodine catalyzed four component reaction at 25°C in water. The yields are excellent, procedure is simple, efficient and environmentally benign.

Page(s): 537-541

Synthesis of 2-aryl-5-(benzofuran-2-yl)-thiazolo[3,2-b][1,2,4]triazoles using green procedures and their antibacterial activity

Mon, 27 Feb 2012 22:58:59 GMT

Title: Synthesis of 2-aryl-5-(benzofuran-2-yl)-thiazolo[3,2-b][1,2,4]triazoles using green procedures and their antibacterial activity

Authors: Jakhar, Komal; Makrandi, J K

Abstract: 3-Aryl-5-(benzofuran-2-yl)acylthio-1,2,4-triazoles 1a-h have been prepared by condensation of 2-(2-bromoacetyl)benzofurans and various 3-aryl-5-mercapto-1,2,4-triazoles under thermal conditions as well as using microwave irradiations and grinding technique. 3-Aryl-5-(benzofuran-2-yl)acylthio-1,2,4-triazoles on cyclisation using polyphosphoric acid under microwave irradiations give 2-aryl-5-(benzofuran-2-yl)-thiazolo[3,2-b][1,2,4]triazoles 2a-h. Preparation of compounds 1a-h using grinding technique and then cyclisation to 2a-h are in accordance to green procedures as these avoid use of hazardous organic solvents during the reaction as well as at its work-up stage. The antibacterial activity of these compounds has been described.

Page(s): 531-536

Microwave assisted green synthesis of novel spiro isoxazolidine derivatives with α-chloro nitrones

Mon, 27 Feb 2012 22:58:59 GMT

Title: Microwave assisted green synthesis of novel spiro isoxazolidine derivatives with α-chloro nitrones

Authors: Chakraborty, Bhaskar; Sharma, Prawin Kumar

Abstract: Microwave assisted 1,3-dipolar cycloaddition reaction of -chloro nitrones to novel -N-methyl and -N-phenylfuran derivative affords exclusively single regioselective 5-spiro isoxazolidines while the same reaction with -methylene--butyrolactone affords two diastereomeric 5-spiro isoxazolidines with high selectivity.

Page(s): 525-530

Synthesis of new 2-(substituted)-5-methyl-2,3-dihydro-1,3,2 λ⁵-benzoxazaphosphol-2-ones

Mon, 27 Feb 2012 22:58:59 GMT

Title: Synthesis of new 2-(substituted)-5-methyl-2,3-dihydro-1,3,2 λ⁵-benzoxazaphosphol-2-ones

Authors: Venkateswarlu, C; Satynarayana, P V V; Rao, C V Nageswara; Raju, C Naga

Abstract: Synthesis and spectral analysis of compounds 3-8 have been described. The synthesis of 2-substituted-5-methyl-2,3-dihydro-1,3,2λ⁵- benzoxazaphosphol-2-ones has been accomplished in a two-step process. In the first step 4-methyl-2-aminophenol is condensed with phosphoryl chloride in benzene in presence of TEA. The intermediate formed in this step is treated with various phenols and aromatic amines to afford the final products. The structure of these compounds is confirmed from analytical and spectral data (IR, ¹H, ¹³C, ³¹P NMR and mass).

Page(s): 521-524

NISCAIR Online Periodicals Repository Collection: IJC-B Vol.51B(03) [March 2012]

One-pot, multicomponent synthesis of 4H-pyrano[2,3-c]pyrazoles in water at 25°C

Synthesis of 2-aryl-5-(benzofuran-2-yl)-thiazolo[3,2-b][1,2,4]triazoles using green procedures and their antibacterial activity

Microwave assisted green synthesis of novel spiro isoxazolidine derivatives with α-chloro nitrones

Synthesis of new 2-(substituted)-5-methyl-2,3-dihydro-1,3,2 λ5- benzoxazaphosphol-2-ones

Synthesis of new 2-(substituted)-5-methyl-2,3-dihydro-1,3,2 λ⁵-benzoxazaphosphol-2-ones