(R)-tert-butyl (1-hydroxybut-3-yn-2-yl) carbamate, an key intermediate of the natural product jaspine B which was isolated from various sponges and endowed with cytotoxic activity against several human carcinoma cell lines, was synthesized fromL-Serine in overall yield 41% through seven steps, including esterification, Boc protection, acetonization, reduction,Corey-Fuchs reaction and deprotection.