Abstract
ROTATIONAL and other data from the synthesis of an optically active derivative1 have shown that 4-methylene-proline (I) isolated under non-epimerizing conditions from loquat seeds2 is racemic. The suspected biogenetic precursor, γ-methyleneglutamic acid, on the other hand, has been found only in optically active form3, although in different plant sources4. In view of the rare occurrence of racemic amino-acids in Nature we wish to record the following simple synthesis of 4-methylene-DL-proline, along with direct comparison evidence confirming its identity with the natural compound. 
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Bethell, M., Kenner, G. W., and Shepperd, R. C., Nature, 194, 864 (1962).
Gray, D. O., and Fowden, L., Nature, 193, 1285 (1962).
Wailes, P., Whiting, M. C., and Fowden, L., Nature, 174, 130 (1954).
Done, J., and Fowden, L., Biochem. J., 51, 451 (1952). Zacharius, R. M., Pollard, J. K., and Steward, F. C., J. Amer. Chem. Soc., 76, 1961 (1954). Harris, G., Chem. and Indust., 244 (1954).
Mooradian, A., and Cloke, J. B., J. Amer. Chem. Soc., 67, 942 (1945). Cf. Burgstahler, A. W., and Aiman, C. E., Chem. and Indust., 1430 (1962).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
BURGSTAHLER, A., TROLLOPE, M. & AIMAN, C. Synthesis of 4-Methylene-DL-proline: a Naturally Occurring Racemic Amino-acid. Nature 202, 388–389 (1964). https://doi.org/10.1038/202388b0
Issue Date:
DOI: https://doi.org/10.1038/202388b0
- Springer Nature Limited