Kuguacin

A kuguacin is one of several chemical compounds isolated from the bitter melon vine (Momordica charantia, kǔguā in Chinese) by J.-C. Chen and others. Kuguacins are cucurbitacins, formally derived from the triterpene hydrocarbon cucurbitane. They include:

Kuguacin A Kuguacin B Kuguacin C Kuguacin D Kuguacin E Kuguacin F: C30H42O5; 47 mg/kg, needles, melts at 275–276 °C Kuguacin G: C30H44O6; 23 mg/kg, needles, melts at 250–252 °C Kuguacin H: C30H44O5; 27 mg/kg, needles, melts at 226–228 °C Kuguacin I: C31H46O4; 20 mg/kg, needles, melts at 235–237 °C Kuguacin J: C30H46O3; 243 mg/kg, powder, melts at 166–169 °C Kuguacin K: C25H34O6; 130 mg/kg, powder, melts at 275–277 °C Kuguacin L: C25H36O4; 30 mg/kg, needles, melts at 320–321 °C Kuguacin M: C22H28O4; 7 mg/kg, needles, melts at 332–333 °C Kuguacin N: C30H46O4; 247 mg/kg, powder, melts at 140–143 °C Kuguacin O: C30H42O4; 20 mg/kg, needles, melts at 267–269 °C Kuguacin P: C27H40O4; 293 mg/kg, prisms, melts at 229–231 °C Kuguacin Q: C29H44O5; 11 mg/kg, needles, melts at 219–221 °C Kuguacin R: C30H48O4; 1357 mg/kg Kuguacin S: C30H44O4; 17 mg/kg, powder, melts at 174–177 °C Kuguacins F-S can be extracted with ethanol from the stems and leaves of M. charantia. Kuguacins I, J, and Q are artifacts of the extraction process. Kuguacin R is obtained as mixture of two epimers. In this process one also obtains momordicine I, kuguacin E, 5β,19-epoxycucurbita-6,23-diene-3β,19,25-triol, karavilagenin D, 3β,7β,25-trihydroxycucurbita-5,(23E)-dien-19-al, and 3β,7β-dihydroxy-25-methoxycucurbita-5,(23E)-dien-19-al In vitro tests showed weak anti-HIV activity for kuguacins F-S, especially kuguacin Q and kuguacin S.

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