The active fraction was concentrated in vacuo to an aqueous
solution and lyophilized to yield 1.62 g of crude powder KB425796-A
(1). The powder was dissolved in 2 ml methanol and applied to the
top of a silica gel 60 column (40/50 mm, 50 ml; Kanto Chemical Co.,
Ltd., Tokyo, Japan) packed with chloroform. The column was eluted
with a mixture of chloroform-methanol (10:1, 150 ml), and fractions
containing KB425796-A (1) were collected and dried to give 1.50 g of
white powder KB425796-A (1).