摘要 |
Compounds are described of the following formula <IMAGE> in which R1 and R2 are each hydrogen, C1-12 alkyl or C2-12 alkenyl, at least one of R1 and R2 being C1-12 alkyl or C2-12 alkenyl; X1 and X2 are each hydrogen or a protecting group; and Y is (a) -(CH=CH)nZ in which n is 1, 2 or 3 and Z is -CHO, -CH2OH, -COR3, -(CH2)m-COR3 or -(CH2)pCH=CH(CH2)q-COR3 in which m is an integer of 1 to 12, p is an integer of 1 to 4, q is an integer of 1 to 10 and R3 is (i) -OH or (ii) -NR4R5 where R4 and R5 are each hydrogen, C1-4 alkyl or optionally substituted phenyl, or R4 and R5 together with the nitrogen atom to which they are attached form a morpholino, pyrrolidinyl or piperidino ring, (b) -CH=NR6 in which R6 is (i) -OH, (ii) C1-12 alkyl optionally substituted by -OH, -COOH or -NR7R8 where R7 and R8 are each hydrogen or C1-4 alkyl, (iii) optionally substituted phenyl or (iv) -NR9R10 in which R9 is hydrogen and R10 is optionally substituted phenyl or C1-4 alkyl CO-, or in which R9 and R10 together with the nitrogen atom to which they are attached form a morpholino, pyrrolidinyl or piperidino ring, (c) -CH2NHR11 in which R11 is C1-12 alkyl optionally substituted with hydroxy or carboxy or optionally substituted phenyl, or (d) -CHOHR12 or <IMAGE> in which R12 is hydrogen or C1-12 alkyl; and lactones, salts and esters thereof; provided that when one of R1 and R2 is hydrogen and the other is C1-12 alkyl, Y is -(CH=CH)nZ, n is 1 and Z is -COOH only salts are included. The compounds have pharmaceutical activity. |