| abstract |
NEW MATERIAL:A compound expressed by formula I {R<1> and R<2> are H, bromine or nitro; R<3> is H, lower alkyl, aralkyl or -(CH2)nZ [Z is OH or formula II (R<4> and R<5> are H, lower alkyl, etc.), etc.]; X is carboxyl, lower alkoxycarbonyl, carbamoyl, hydroxymethyl, etc.; Y is OH, lower alkoxy or aralkyloxy, provided that X and Y together represent formula III or IV} and salt thereof. USE:A antiallergic agent, antithrombotic agent, anti-inflammatory agent, antitumor agent, etc., having powerful inhibitory activity against C-kinase. PREPARATION:A raw material compound expressed by formula V, such as a physiologically active substance K-252, is reacted with an oxidizing agent (e.g. Collins' reagent consisting of chromic acid dipyridine complex) in an amount of 5-7 equiv. based on the above-mentioned compound in pyridine solvent at 0 deg.C - room temperature for 1 day. |