| 摘要 |
There is provided a compound comprising the general structure (I) in which, X is N or O; R3 is OR4 or R4; wherein when X is N, R1 is H, R5 or OR6; R2 is OC(O)R7; and R4 is R5, OR5 or aryl, which is unsubstituted or substituted with at least one of R5 or OR6, OC(O)R7, C(O)R8, OR9, C(H)(OR')2 or C(R10)(OR')2; wherein when X is O, R2 is absent; R1 is H, R5 or OR6, CH(OR8)R9; and R4 is R5, OR5 or aryl, which is unsubstituted or substituted with at least one of R5 or OR6, OC(O)R7, C(O)R8, OR9, C(H)(OR')2 or C(R10)(OR')2; wherein R5, R6, R7, R8, R9, and R10 are independently selected from linear or branched C1–C20 alkyl or OH; and R' is independently selected from linear or branched C1–C20 alkyl, or may together form a cyclic aliphatic ring having from 2 to 40 carbon atoms. |
