3- Oxo-l,8-cineole

Based on the aforementioned results, it is obvious that (+)-3p-hydroxy-l,8-cineole (123b) is formed mainly in the biotransformation of 1,8-cineole (122), (+)-3a-hydroxy-l,8-cineole (123b), and (+)-3-oxo-l,8-cineole (126a) by S. ikutamanensis Ya 2 1. The production of (+)-3p hydroxy-l,8-cineole (123b) is interesting, because it is a precursor of mosquito repellent, p-menthane-3,8-diol (142aa ) (Noma and Nishimura, 1981) (Figure 19.136). 

Figure 4.8. The GC/MS-EI (70eV) SCAN mode chromatogram of compounds formed by acid hydrolysis of a Raboso grape skins extract. Peak 1. frans-furanlinalool oxide peak 2. cfs-furanlinalool oxide I.S.l, internal standard (1-octanol) peak 3. (Z)-ocimenol peak 4. ( )-ocimenol peak 5. a-terpineol I.S.2, internal standard (1-decanol) peak 6. 2-exo-hydroxy-l,8-cineol peak 7. benzyl alcohol peak 8. P-phenylethanol peak 9. actinidols A peak 10. actinidols B peak 11. endiol peak 12. eugenol peak 13. vinylguaiacol peak 14. p-menthenediol I peak 15. 3-hydroxy-P-damascone peak 16. vanillin peak 17. methyl vanillate peak 18. 3-oxo-a-ionol peak 19. 3-hydroxy-7,8-dihydro-P-ionol peak 20. homovanillic alcohol peak 21. vomifoliol.

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