Patent ID: 7132559

Claim:
A compound represented by A: wherein X represents O, S, N(R 2 ), or C(R 3 ) 2 ; R represents independently for each occurrence H, alkyl, aryl, heteroaryl, heteroaralkyl, formyl, acyl, alkoxycarbonyl, aralkoxycarbonyl, alkylaminocarbonyl, or aralkylaminocarbonyl; R 2 represents independently for each occurrence H, alkyl, aryl, heteroaryl, aralkyl, heteroaralkyl, formyl, acyl, alkoxycarbonyl, aralkoxycarbonyl, alkylaminocarbonyl, or aralkylaminocarbonyl; R 3 represents independently for each occurrence H, alkyl, aryl, heteroaryl, aralkyl, heteroaralkyl, formyl, acyl, alkoxycarbonyl, aralkoxycarbonyl, alkylaminocarbonyl, or aralkylaminocarbonyl; R′ represents H, alkyl, aryl, heteroaryl, aralkyl, or heteroaralkyl; or XR′ represents halide; the stereochemical configuration at any stereocenter of a compound represented by A may be R, S, or a mixture of these configurations; and the enantiomeric excess of a compound represented by A is greater than or equal to about 95%.