It is established that the condensation of 2-hydroxy-4:6:2′-trimethoxy phenyl benzyl ketone and its 3-methyl derivative with ethyl formate as well as with methyl formate produces the corresponding 2-hydroxy isoflavanones. These undergo dehydration to the trimethyl ether of isogenistein and 8-methyl isogenistein respectively. Demethylation of the above ethers can be conveniently effected by aluminium chloride in benzene solution. The 2-hydroxy isoflavanones also yield the same products by undergoing dehydration along with demethylation.