Synthesis from calcium D-gluconate

Numata, A. Ibuka, T. In The Alkaloids, Vol. 31 Brossi, A., Ed. Academic Rress New York, 1985 Chapt. 

Breyer-Brandwijk, M.G. The Medicinal and Poisonous Plants of Southern and Eastern Africa, 2nd ed. E S Livingstone London, 1962. 

5-Dihydroxypipecolic acid (2) was isolated from the leaves of Derris eliptica  

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