Geijera parviflora

Geiparvarin (898) isolated from Geijera parviflora, reported to have antitumor properties, was first synthesized by Smith et al., who thereby also established the stereochemistry of the double bond. The synthesis consisted of the aldol addition of the aldehyde 899 (R = CH2CHO), prepared from umbelliferone (899, R = H), to 5-ethyl-2,2-dimethyl-2/f-furan-3-one (900) when both isomers of 898 were obtained, the ( )-isomer being identical to the natural product. The synthesis of Jackson and Raphael (Scheme 67) starts with the acetylenic alcohol 901, once readily available, but no longer, because of the hazards associated with its handling (cf. Vol. 4, p. 558, Ref. 733). The... 

CigHigOj, Mr 326.35, crystals, mp. 157-158 °C (E-form). Antitumor principle from the leaves of Geijera parviflora (Rutaceae). A dihydro form with a hydrogenated furanone ring, C19H20OS, Mr 328.36, also isolated from G. parviflora and possessing cytostatic activity is known as well. ... 

Shou QY, Banbury LK, Renshaw DE, Smith JE, He XX, Dowell A, et al. Parviflor-anines A and B, two 11-carbon alkaloids from Geijera parviflora. J Nat Prod 2013 76(7) 1384-7. 

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