220468-39-3Relevant academic research and scientific papers
Synthesis and reactivity of 5,8-dihydroxythioflavanone derivatives
Konieczny, Marek T.,Horowska, Barbara,Kunikowski, Antoni,Konopa, Jerzy,Wierzba, Konstanty,Yamada, Yuji,Asao, Tetsuji
, p. 359 - 364 (2007/10/03)
The synthesis of substituted chalcones, thioflavanones, and thioflavones hydroxylated in both A and B rings is described. Acetoquinone (1) was transformed into 2,5-dihydroxy-6-(p-methoxybenzylmercapto)acetophenone (2) and subsequently into its 2,5-dimethoxy (3) and 2,5-dibenzyloxy (4) derivatives. Compounds 3 and 4 were condensed with suitable benzaldehydes to give chalcones 5-10. The thiol group of the chalcones was deprotected by a cleavage of the p-methoxybenzyl protecting group using a new, mild method (silver nitrate in boiling ethanol, 2 h), and the products were cyclized to thioflavanones (15-20). Dehydrogenation of the thioflavanones gave related thioflavones (25-27). Deprotection of methoxy and benzyloxy groups is also described.
