Efficient Synthesis of Glycosylated Matijin-Su Derivatives via Ultrasonic Irradiation

Matijin-Su ( 1 ) is a phenylalanine dipeptide compound with anti-hepatitis B virus (HBV) activity. Previous reports suggest that the synthesis of glycosylated Matijin-Su derivatives needs at least 10 steps. To simplify the synthetic procedure, we have developed a shorter and more efficient method for the preparation via ultrasound irradiation. Two galactopyranosylated ( 2 ) and two glucopyranosylated ( 3 ) derivatives were synthesized in 6 or 7 steps. The overall yields for the total synthesis of galactopyranosylated derivatives were markedly increased to 39% ( 2a ) or 22% ( 2b ). And the yields for glucopyranosylated derivatives also reached 29% ( 3a ) or 16% ( 3b ).