Abstract:
A compound of the formula: ##STR1## wherein: each of R. sub. 1, R. sub. 1 ', R. sub. 2 and R. sub. 2 ' independent of each other is a substituted or unsubstituted, branched or linear C. sub. 1-12 alkyl, alkene or alkyne group, R. sub. 3 is OH, OCH. sub. 3, CH. sub. 2 COOH or ##STR2## wherein each of R. sub. 2" and R. sub. 2 '41 independent of each other is a substituted or unsubstituted, branched or linear C. sub. 1-12 alkyl, alkene or alkyne group and: A=NH. sub. 2, X=P(OH), Y=Z=C, B=OCH. sub. 3, or A=OH, X=P(OH), X=Z=C, B (if present)=OCH. sub. 3, or A=OCO(CH. sub. 2). sub. n NH. sub. 2, X=P(OH), Y=Z=C, B=OCH. sub. 3, wherein n=1-10, or A=OH, X=P(OH), Y=Z=C, B=O(CH. sub. 2). sub. n CO. sub. 2 H, wherein n=1-10, or A=OH, X=P(OH), Y=Z=C, B=(CH. sub. 2). sub. n CO. sub. 2 H, wherein n=1-10, or A=NH. sub.