NEW MATERIAL:The quinone derivative of formula I (m is 11W22; R1 is lower alkyl; R2 is H, lower alkyl, or lower acyl).

EXAMPLE: 6-(13-Hydroxytridecyl)-2,3-dimethyoxy-5-methyl-1,4-benzoquinone.

USE: It has hypotensive, tissue metabolism activating, immuno-regulating, lysosome membrane stabilizing, and anti-SRS-A activities, and useful as, e.g. a remedy for cardiac insufficiency, remedy for cerebral circulation disorder, immuno-regulating agent, anti-allergic agent, etc. for mammals including manking.

PROCESS: The compound of formula I is prepared by oxidizing the compound of formula II (R4 is lower alkyl or lower alkoxy, or two R4 groups together form one CH=CH-CH=CH group; n is 9W20; A is CH2, etc.; one of X1 and X2 is hydroxyl group or amino group, and the other is H, etc.) with oxygen or air in the presence of a transition metal complex.