Ashry ESHE, Kassem AA, Abdel-Hamid H, Louis FF, Khattab SAN, Aouad MR. Novel regioselective formation of S- and N-hydroxyl-alkyls of 5-(3-chlorobenzo[b]thien-2-yl)-3-mercapto-4H-1,2,4-triazole and a facile synthesis of triazolo-thiazoles and thiazolo-triazoles. Role of catalyst and microwave.
NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2007;
26:437-51. [PMID:
17578742 DOI:
10.1080/15257770701426187]
[Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Regioselective alkylation of 5-(3-chlorobenzo[b]thien-2-yl)-4H-1,2,4-triazole (1) with hydroxy alkylating agents 2, 3, 13, and the 2,3-O-isopropylidene-1-O-(p-tolylsulfonyl)-glycerol (10) afforded the corresponding S-alkylated derivatives 6, 7, 11, and 14 under both conventional and microwave irradiation conditions; bentonite as a solid support gave better results, with no change in regioselectivity. A facile intramolecular dehydrative ring closure of 6, 7, 11, and 14 using K(2)CO(3) in DMF afforded the corresponding fused triazolo-thiazines and thiazolo-triazole 17-19. The isopropylidenes and acetyl derivatives of the products were prepared.
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