PURPOSE: To obtain a new compound, having low toxicity and useful as a hypotensive agent, an analgesic agent, an antiulcer agent, an antiinflammatory agent, an immunomodulator, an ameliorant for cerebral circulatory systems, etc.

CONSTITUTION: The compound of formula I [R1and R2 are methyl or methoxy or R1 and R2 are bound to form CH=CH-CH=CH; either of A and B is (substituted)alkyl, acyl, alkoxycarbonyl, etc., and the other is H; X is H, aryl or heterocyclic residue; R is 1-20C bivalent hydrocarbon residue when X is H and 1-20C bivalent hydrocarbon residue or direct bond when X is others; Y is H when X is H and either of A and B is sulfo, H or (substituted) hydroxymethyl when X is H and either of A and B is glycosyl and H, carboxyl, etc., in other cases], e.g. 2,3-dimethoxy-4-hydroxy-6-(10-hydroxydecyl)-5- methylphenyl 1-phosphate. Furthermore, this compound of formula I is obtained by deprotecting a compound of formula III (R3 is OH-protecting group) obtained from, e.g. a compound of formula II as a starting raw material.