Patent ID: 6958319

Claim:
A compound of the formula (1): wherein P is hydrogen or an amino-group protecting moiety; R is hydrogen or alkyl; A is 0, 1, or 2; R 1 , R 2 , and R 3 are each independently hydrogen, alkyl, cycloalkyl, aryl, or —CH 2 —R 5 ; R 5 , in each instance, is aryl, aralkyl, alkaryl, cycloalkyl, heterocyclyl, heteroaryl, or —W—R 6 , where W is a chalcogen and R 6 is alkyl; wherein the ring portion of any said aryl, aralkyl, alkaryl, cycloalkyl, heterocyclyl, or heteroaryl in R 1 , R 2 , R 3 , or R 5 can be optionally substituted; and Z 1 and Z 2 together form a moiety derived from a sugar, wherein the atom attached to boron in each case is an oxygen atom.