| 摘要 |
Immunologically active compounds of the formula: <IMAGE> (I.) hydrogen; C1-30 alkyl; C2-30 alkenyl; C1-30 alkoxy; phenyl; C1-20 alkylsulfonyl; or cholesteryl; and R4 may additionally be hydrogen; R5 is hydrogen; or R5-R6 together is -CH2-CH2-CH2; R6 is hydrogen; C1-7 alkyl; hydroxymethyl; mercapto-methyl; benzyl; or substituted benzyl; R7 and R8 may be the same or different and are each independently COOR or CONR'R'', where R is hydrogen or C1-7 alkyl, and R' and R'' are each independently hydrogen or C1-3 alkyl; when R2 is C1-10 alkyl, the stereochemistry at asymmetric center I can be either D or L; when R6 is not hydrogen, the stereochemistry at asymmetric center Ii is L; the stereochemistry at asymmetric center III is D. |
