Insect antifeedants from parabenzoin trilobum (I) two new sesquiterpenes, shiromodiol-diacetate and -monoacetate

✍ Scribed by Kojiro Wada; Yuji Enomoto; Kuniaki Matsui; Katsura Munakata

• Book ID: 104223064
• Publisher: Elsevier Science
• Year: 1968
• Tongue: French
• Weight: 177 KB
• Volume: 9
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)89903-7

✦ Synopsis

The leaves of Parabenzoin trilobum Nakai are not eaten by a polyphagous insect, Prodenia litura Fabricius on the laboratory test. The benzene extract of the leaves of P. trilobum have shown distinct antifeeding activity against P. litura on the preiiminary experiment. Recently, we succeeded to isolate two active principles from the dried leaves, and named -them shirancdiol-diacetate and monoacetate respectively. Shircmodiol-diacetate and -monoacetate showed 10% antifeeding activity against P. litura at O.% concentration respectively. On entanological test against a Oligophagous insect, Trimeresia miranda Butler, the former showed 10% antifeeding activity at 0.1% concentration, while the latter showed only weak activity even at 11 0.2% . .This paper presents evidence which let us assign the structure (I) and (II) for shiromodioldiacetate and -monoacetate respectively. Shiromodiol-diacetate (I), C19H3005 (elementary analysis and mass), has m.p. 112OC, (a);5 -61.9o (c, 1.06 CHC131, );KB 1735 and 1240 cm -1