ODA Kazuaki HEALTH SCIENCES UNIVERSITY OF HOKKAIDO,FACULTY OF PHARMACEUTICAL SCIENCES,INSTRU, 薬学部, 助手 (80094829)
TAKECHI Haruko HEALTH SCIENCES UNIVERSITY OF HOKKAIDO,FACULTY OF PHARMACEUTICAL SCIENCES,ASSIST, 薬学部, 講師 (70094836)
|Budget Amount *help
¥1,600,000 (Direct Cost: ¥1,600,000)
Fiscal Year 1995: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 1994: ¥900,000 (Direct Cost: ¥900,000)
Photoreaction of arenecarbothioamides with substituted furans.
As part of our continuing program to investigate photochemistry of the nitrogen-thiocarbonyl systems, the photoreactions of arenecarbothioamides with carbon-carbon double bond (alkene) systems were studied. In particular, furans as a cycloalkadiene analogue (Paterno-Buchi acceptor) showed interesting photochemical behavior towards arenecarbothioamide to afford various heterocyclic compounds. In the case of 5-membered heteroaromatics (furan, thiophene, or 1-phenylsulfonylpyrrole), arenecarbothioamides gave regioselectively the corresponding 3-aroyl derivatives in good yields as major reaction. But in a case of 2-alkoxyfuran, henzannulation reaction occurred in preference to aroylation, giving benzo-fused heteroaromatics such as benzofuran, benzothiophene, isoquinoline, and quinoline, In photoreaction of thiobenzamide with certain furans, both transformation of furans to pyrroles and benzannulation occurred in preference to benzoylation.
In photoreaction of thiobenzamide with 2-vinylfuran analogues, tetracyclic indole derivative was obtained. This photoreaction would provide a new and convenient single-step convergent annulation approach for the construction of a multicyclic indole system.
(2) Photoreaction of thiobarbiturates.
Intermolecular photoreaction of mono-, di-, and tri-thiobarbiturate with alkenes gave efficiently thietanes. Similarly, intramolecular photoreaction of thiobarbiturates having an alkenyl group in their N-side chain gave fused pyrimidine derivatives through photocyclization.