38445-23-7Relevant articles and documents
One-Pot Synthesis of B-Ring Ortho-Hydroxylated Sappanin-Type Homoisoflavonoids
Mrug, Galyna P.,Myshko, Nataliia V.,Bondarenko, Svitlana P.,Sviripa, Vitaliy M.,Frasinyuk, Mykhaylo S.
, p. 7138 - 7147 (2019)
A reliable method for the synthesis of B-ring hydroxylated homoisoflavonoids and 3-hetarylmethyl chromones has been developed. The method involves an initial oxa-Diels-Alder reaction of ortho-quinone methides generated from aryl/hetaryl-substituted ortho-(N,N-dimethylaminomethyl)phenols with (2E)-3-(N,N-dimethylamino)-1-(2-hydroxyphenyl)prop-2-en-1-ones and the subsequent cascade of reactions. This synthetic strategy avoids conventional multistep protocols and does not require the protection of hydroxyl groups, thus allowing the facile synthesis of a library of various aromatic and heterocyclic analogues of naturally occurring homoisoflavonoids.
Benzopyrans : Part 40 - Alumina mediated transformations of 4-oxo-4H-1- benzopyran-3-carbaldehyde, -3-carboxylic acid and their 2-methylhomologues
Ghosh, Chandra Kanta,Bhattacharyya, Samita
, p. 166 - 172 (2007/10/03)
In contact with alumina, the title aldehyde 1 (R = H, Me, Cl) gives the chromones 5 and 9,12 whereas the acid 2 affords the chromones 7, 10 and acetophenone 23. Alumina converts the aldehyde 3 to the xanthone 14, and the corresponding acid 4 to the chromone 8 and diketone 24.