• Archives of Pharmacal Research
• /
• v.16 no.4
• /
• pp.339-342
• /
• 1993

3-Oxo or/and 11-oxo derivatives of natural 3-hydroxy triterpense, i.e., 3-oxoursolic acid la, 11-oxoursolic acid lb, 3, 11-dioxoursolic acid ic, 3-oxobetulinic acid lla and 3-oxopomolic acid Via were exhibited to show an increased anti-HSV-1 activity in vitro, four to ten times as much as corresponding parent 3-hydroxy compounds.