A compound of the following structure: wherein R.sup.1 is H, an alkyl
group, an aryl group, an alkenyl group, an alkynyl group, or a halogen
atom; R.sup.2 is H, an alkyl group, an aryl group, a benzyl group, a
trityl group, --SiR.sup.aR.sup.bR.sup.c, CH.sub.2OR.sup.d, or COR.sup.e;
R.sup.a, R.sup.b and R.sup.c are independently an alkyl group or an aryl
group; R.sup.d is an alkyl group, an aryl group, an alkoxylalkyl group,
--R.sup.iSiR.sup.aR.sup.bR.sup.c or a benzyl group, wherein R.sup.i is an
alkylene group; R.sup.e is an alkyl group, an allyl group, a benzyl
group, an aryl group, an alkoxy group, or --NR.sup.gR.sup.h, wherein
R.sup.g and R.sup.h are independently H, an alkyl group or an aryl group;
R.sup.3 is (CH.sub.2).sub.n where n is and integer in the range of 0 to
5, --CH.sub.2CH(CH.sub.3)--, --CH.dbd.CH--, --CH.dbd.C(CH.sub.3)--, or
--C.ident.C--; R.sup.4 is (CH.sub.2).sub.p where p is an integer in the
range of 4 to 12,
--(CHR.sup.k1).sub.y1(CHR.sup.k2).sub.y2(CHR.sup.k3).sub.y3(CHR.sup.k4).s-
ub.y4(CHR.sup.k5).sub.y5C(R.sup.s1).dbd.C(R.sup.s2)C(R.sup.s3).dbd.C(R.sup-
.s4)--, --(CHR.sup.k1).sub.y1(CHR.sup.k2).sub.y2(CHR.sup.k3).sub.y3(CHR.su-
p.k4).sub.y4(CHR.sup.k5).sub.y5CH(R.sup.s1)CH(R.sup.s2)C(R.sup.s3).dbd.C(R-
.sup.s4)--,
--(CHR.sup.k1).sub.y1(CHR.sup.k2).sub.y2(CHR.sup.k3).sub.y3(CHR.sup.k4).s-
ub.y4(CHR.sup.k5).sub.y5C(R.sup.s1).dbd.C(R.sup.s2)CH(R.sup.s3)CH(R.sup.s4-
)--, --(CHR.sup.k1).sub.y1(CHR.sup.k2).sub.y2(CHR.sup.k3).sub.y3(CHR.sup.k-
4).sub.y4(CHR.sup.k5).sub.y5CH(R.sup.s1)CH(R.sup.s2)CH(R.sup.s3)CH(R.sup.s-
4)--, wherein y1 and y2 are 1 and y3, y4 and y5 are independently 0 or 1,
R.sup.k1, R.sup.k2, R.sup.k3, R.sup.k4 and R.sup.k5 are independently H,
CH.sub.3, or OR.sup.2a, and R.sup.s1, R.sup.s2, R.sup.s3, and R.sup.s4
are independently H or CH.sub.3, wherein R.sup.2a is H, an alkyl group,
an aryl group, a benzyl group, a trityl group, --SiR.sup.aR.sup.bR.sup.c,
CH.sub.2OR.sup.d, or COR.sup.e; and R.sup.5 is H or OR.sup.2b, wherein
R.sup.2b is H, an alkyl group, an aryl group, an aryl group, a benzyl
group, a trityl group, --SiR.sup.aR.sup.bR.sup.c, CH.sub.2OR.sup.d, or
COR.sup.e; provided that the compound is not dictyostatin 1.