a L-5-monosubstituted hydantoin => a D-5-monosubstituted hydantoin
a l-5-monosubstituted hydantoin => a d-5-monosubstituted hydantoin
a L-5-monosubstituted hydantoin => a D-5-monosubstituted hydantoin
a l-5-monosubstituted hydantoin => a d-5-monosubstituted hydantoin