Tetradenia riparia

The essential oils of some plants from Kenya were evaluated for mosquito repellence against Anopheles gambiae on the forearms of human volunteers. The oils of Croton pseudopulchellus, Mkilua fragrans, Endostemon teresticaulis, Ocimum forskolei, Ocimum fischeri, Plectranthus longipes, Conyza newii and Plectranthus marrubioides were all found to be more potent than DEBT, the synthetic repellant. The activity of each of the oils of Lippia javanica, Lippia ukambensis and Tetradenia riparia was similar to that of DEBT, but the oil of Tarchonanthus camphoratus was less potent (87,88). 

Gazim, Z. C., Rodrigues. F., Amorin, A. C., de Rezende, C. M., Sokovic, M Tesevic, V. et al. (2014). New natural diterpene-type abietane from Tetradenia riparia essential oil with cytotoxic and antioxidant activities, 19, 514 524. 

Umuravumbolide (28) and desacetylumuravumbolide (28a) are a-pyrone containing natural products isolated from Tetradenia riparia found in Rwanda (Central Africa) (62). So far, no synthesis has been reported for this molecule. Our synthesis of this molecule involves Alpine-Borane mediated asynunetric reduction of heptyn-3-one, followed by formylation, Lindlar reduction, allylboration with 1, and ring-closing metathesis using Grubbs catalyst as key steps (Scheme 10) 11),... 

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