NOPR Collection:

Chemoselective tetrahydropyranylation of primary alcohols under freezing water pressure

2010-05-14T16:31:08Z

Title: Chemoselective tetrahydropyranylation of primary alcohols under freezing water pressure Authors: Boruwa, Joshodeep; Bhuyan, Ranjana; Gogoi, Naminita; Barua, Nabin C Abstract: A highly efficient environmentally friendly method for selective tetrahydropyranylation of primary alcoholic groups under pressure exerted by freezing water has been described. Page(s): 331-334

Synthesis of anhydrides from acyl halides and zinc carboxylates under aprotic conditions

2010-05-16T16:30:47Z

Title: Synthesis of anhydrides from acyl halides and zinc carboxylates under aprotic conditions Authors: Pasha, M A; Rizwana, S Abstract: Synthesis of symmetric as well as unsymmetrical carboxylic acid anhydrides from zinc carboxylates and acid chlorides under aprotic conditions in high yields is reported. Page(s): 420-421

A new lupene-type triterpene from the leaves of Orthosiphon stamineus

2010-05-21T16:30:34Z

Title: A new lupene-type triterpene from the leaves of Orthosiphon stamineus Authors: Hossain, M Amzad; Ismail, Zhari Abstract: Orthosiphonoic acid, a new lupine-type triterpene isolated from the leaves of local Orthosiphon stamineus by thin layer chromotography, has been identified as 16β-hydroxybetulinic acid by GC coupled with mass spectrometry, UV, IR and ¹HNMR spectroscopy. Page(s): 436-437

Facile synthesis of some new azetidinones and acetyl oxadiazoles bearing benzo[b]thiophene nucleus as a potent biological active agent

2010-05-22T16:30:34Z

Title: Facile synthesis of some new azetidinones and acetyl oxadiazoles bearing benzo[b]thiophene nucleus as a potent biological active agent Authors: Vasoya, S L; Patel, M R; Dobaria, S V; Joshi, H S Abstract: 2-Hydrazinocarbonyl-3-chloro-5-phenoxybenzo[b]thiophene 1 has been prepared by the condensation of 3-chloro-5-phenoxybenzo[b]thiophenoyl chloride with hydrazine hydrate. Compound 1 on condensation with aromatic aldehyde furnishes 2-substituted benzalhydrazinocarbonyl-3-chloro-5-phenoxybenzo[b]thiophenes 2a-l, which on further cyclocondensation with chloroacetyl chloride in the presence of triethyl amine afford 4-aryl-3-chloro-1-(3'-chloro-5'-phenoxy-2'-benzo[b]thiophenoylamino)-2-azetidinones 3a-l. Compounds 2a-l on reaction with acetic anhydride yield 2-(3'-chloro-5'-phenoxybenzo[b]thiophene-2'-yl)-4-acetyl-5-aryl-4,5-dihydro-1,3,4-oxadiazoles 4a-l. The structures of the compounds 2a-l, 3a-l and 4a-l have been confirmed by elemental analysis and IR, ¹H NMR and mass spectral data. All the compounds have been screened for their antitubercular activity towards Mycobacterium tuberculosis H₃₇Rv and antimicrobial activity against different microbes. Page(s): 405-409