NEW MATERIAL:The compound of formula I (R1 is H, OH or lower alkoxy; R2 is 1W4C alkyl).

EXAMPLE: The compound of formula II.

USE: An intermediate of aklavinone-group compound, from which an aclacinomycin-group compound can be synthesized easily by enzymatic glycosidation.

PROCESS: The compound of formula I can be prepared by (1) bonding the compound of formula III (X is Br or Cl) with the compound of formula IV by Diels- Alder reaction, (2) oxidizing the resultant condensate to the compound of formula V, (3) oxidizing the compound with ozone, (4) reacting the resultant aldehyde compound with D-(-)-2,3-butanediol to obtain the compound of formula VI, (5) subjecting the compound to aldol condensation with 1-(trimethylsilyl)-2-butanone, and (6) cyclizing the product. The compound of formula I can be converted to an aklavinone-group compound easily, by treating in, e.g. trifluoroacetic acid at -78W+10°C.