http://nopr.niscpr.res.in/handle/123456789/8770 2026-10-09T20:29:23Z http://nopr.niscpr.res.in/handle/123456789/8958 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 2005-02-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/8957 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 2005-02-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/8956 Title: A new lupene-type triterpene from the leaves of <i>Orthosiphon stamineus</i> Authors: Hossain, M Amzad; Ismail, Zhari Abstract: Orthosiphonoic acid, a new lupine-type triterpene isolated from the leaves of local O<i style="">rthosiphon stamineus </i>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 2005-02-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/8955 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 <b>1</b> has been prepared by the condensation of 3-chloro-5-phenoxybenzo[b]thiophenoyl chloride with hydrazine hydrate. Compound <b>1</b> on condensation with aromatic aldehyde furnishes 2-substituted benzalhydrazinocarbonyl-3-chloro-5-phenoxybenzo[b]thiophenes <b>2a-l</b>, 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 <b>3a-l</b>. Compounds <b>2a-l</b> 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 <b>4a-l</b>. The structures of the compounds <b>2a-l</b>, <b>3a-l</b> and <b>4a-l</b> 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 <i>Mycobacterium tuberculosis </i>H₃₇Rv and antimicrobial activity against different microbes. Page(s): 405-409 2005-02-01T00:00:00Z