67052-53-3Relevant academic research and scientific papers
A catechin preparation method of compound (by machine translation)
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, (2017/02/23)
The invention relates to a method for preparing a catechin compound. The method comprises the following steps: by taking 2,4,6-trihydroxy acetophenone and p-hydroxy benzaldehyde as raw materials, carrying out condensation reaction, restored deoxidation, cyclization reaction of acid catalysis, so as to obtain the catechin compound. The invention also provides a technology for producing the catechin compound. In the synthesis process of an immediate 9, reduction is carried out by using sodium borohydride which is catalyzed by a lewis acid, so that side reaction caused by double bond transfer is greatly reduced while a highly toxic reagent osmium tetroxide is replaced with hydrogen peroxide oxidation.
Microwave-assisted regioselective synthesis of natural 6-prenylpolyhydroxyisoflavones and their hydrates with hypervalent iodine reagents
Hossain, Mohammad M.,Kawamura, Yasuhiko,Yamashita, Kazuyo,Tsukayama, Masao
, p. 8625 - 8635 (2007/10/03)
Microwave-assisted oxidative rearrangement of 3′-iodotetraalkoxychalcones with hypervalent iodine such as [hydroxy(tosyloxy)iodo]benzene or [bis(trifluoroacetoxy)iodo]benzene, followed by microwave-mediated hydrolysis and in situ cyclization of the resultant acetals gave 6-iodotrialkoxyisoflavones. Pd(0)-catalyzed coupling reaction of the 6-iodoisoflavones with 2-methyl-3-butyn-2-ol under microwave irradiation gave 6-alkynylisoflavones, whose hydrogenation gave the respective hydrates of wighteone, lupisoflavone and derrubone. Wighteone (1a), lupisoflavone (1b) and derrubone (1c) were obtained by dehydration of their respective hydrates under microwave irradiation.
Regioselective synthesis of prenylisoflavones. Syntheses of allolicoisoflavone A, 2,3-dehydrokievitone, and related compounds
Tsukayama, Masao,Li, He,Tsurumoto, Ken,Nishiuchi, Masaki,Kawamura, Yasuhiko
, p. 2673 - 2680 (2007/10/03)
The palladium-catalyzed coupling reaction of 2',4',5,7- tetrakis(benzyloxy)-5'-iodolsoflavone (12), synthesized from the 5- iodochalcone 9, with 2-methyl-3-butyn-2-ol gave the corresponding 5'-(3- hydroxy-3-methyl-1-butynyl)isoflavone 13. The catalytic hydrogenation of 13 gave 2',4',5,7-tetrahydroxy-5'-(3-hydroxy-3-methylbutyl)isoflavone (2). Dehydration of the benzoate 14 of 2 afforded a mixture of 5'-(3-methyl-2- butenyl)isoflavone 15 and the isomer 5'-(3-methyl-3-butenyl)isoflavone 16. The separation of 15 was accomplished by a treatment of the mixture (15 and 16) with mercury(II) nitrate. Hydrolysis of 15 afforded 2',4',5,7- tetrahydroxy-5'-prenylisoflavone (allolicoisoflavone A) (1). In a similar manner, 2',4',5,7-tetrahydroxy-8-prenylisoflavone (2,3-dehydrokievitone) (3) and 2',4',5,7-tetrahydroxy-8-(3-hydroxy-3-methylbutyl)isoflavone (2,3- dehydrokievitone hydrate) (4) were synthesized from the corresponding 8- iodoisoflavone 22. The tetramethyl ether 5 of 3 was also prepared from the 8- iodotetramethoxyisoflavone 32.
