27.Assign R or S configuration for the chiral centers in 2,3,4-trihydroxybutanal.

(A) 2R, 3R
(B) 2R, 3S
(C) 2S, 3R
(D) 2S, 3S
(E) this compound is optically inactive.

1. 題目解析題目要求我們為化合物2...