NISCAIR Online Periodicals Repository Collection: IJC-B Vol.45B(06) [June 2006]

Synthesis of 12,13-dihydro-5-oxoquinolino[2,3-a]carbazoles, 3,11-dihydro-2,4-dioxopyrano[2,3-a]carbazoles and quinolino[2,3-b]carbazolo[6,5-a]pyran-7,8-diones

Mon, 29 May 2006 22:58:59 GMT

Title: Synthesis of 12,13-dihydro-5-oxoquinolino[2,3-a]carbazoles, 3,11-dihydro-2,4-dioxopyrano[2,3-a]carbazoles and quinolino[2,3-b]carbazolo[6,5-a]pyran-7,8-diones

Authors: Sangeetha, V; Prasad, K J Rajendra

Abstract: The reaction of 1-hydroxycarbazoles 1a-d with anthranilic acid in the presence of fused zinc chloride and phosphorus oxychloride at room temperature affords 1,7-dibenzoazocin-6,12-dione 2 in all the cases and the expected 12,13 dihydro-5-oxoquinolino[2,3-a]carbazoles 3a-d. In another reaction, 1-hydroxycarbazoles 1a-d with malonic acid in the presence of fused zinc chloride and phosphorus oxychloride at room temperature yields 3,11-dihydro-2,4-dioxopyrano[2,3-a]carbazoles 4a-d. Further, the attempted synthesis of c/b fused quinolinodipyrano annelated carbazoles 7a-d or 8a-d or both from the reaction of 3,11-dihydro-2,4-dioxopyrano[2,3-a]carbazoles 4a-d with vinyl acetate and 2,4-dihydroxyquinoline 6 results in the formation of new dimerised product, quinolino[2,3-b]carbazolo[6,5-a]pyran-7,8-diones 9a-d. A plausible mechanism has been suggested to explain this reaction.

Page(s): 1487-1491

Cytotoxic and antimicrobial activities of some synthetic flavones

Mon, 29 May 2006 22:58:59 GMT

Title: Cytotoxic and antimicrobial activities of some synthetic flavones

Authors: Mostahar, Sohel; Alam, Sayed; Islam, Azizul

Abstract: Several flavones have been synthesized and their biocidal activity investigated along with their corresponding chalcones against some bacterial and fungal strains as well as brine shrimp nauplii. Compounds 13 and 14 show good antibacterial, antifungal and cytotoxic activity against some selected bacterial and fungal strains as well as brine shrimp nauplii. The synthesized compounds have been characterized using UV-Vis, IR, ¹H and ¹³C NMR spectral data together with elemental analysis.

Page(s): 1478-1486

Synthesis of some novel 4-substituted coumarins having potential biological activity (Part III)

Mon, 29 May 2006 22:58:59 GMT

Title: Synthesis of some novel 4-substituted coumarins having potential biological activity (Part III)

Authors: Mashelka, U C; Audi, A A

Abstract: Various methyl substituted coumarin carboxaldehydes have been condensed with aromatic amines to give Schiff bases. These Schiff bases have then been reacted with thioglycolic acid to give five membered cyclized products, 4-thiazolidinone substituted at 4-position of coumarins. 4-alkyl coumarin acetates have been reacted with semicarbazide or thiosemicarbazide in polyphosphoric acid to undergo condensation followed by in situ cyclization to form oxadiazoles and thiadiazoles. All the 4 – substituted coumarin heterocycles have been found to possess antibacterial activity.

Page(s): 1463-1469

Synthesis of homoanisic acid

Mon, 29 May 2006 22:58:59 GMT

Title: Synthesis of homoanisic acid

Authors: Mahajan, S S; Pikle, R P

Abstract: Synthesis of homoanisic acid by Erlenmeyer condensation via the formation of azalactone is discussed.

Page(s): 1554-1556