Acacia willardiana

In 1959 a new non-protein L-a-amino acid was isolated from the seeds of Acacia willardiana and later from other species of Acacia-, it proved to be l-/3-amino-/3-carboxyethyluracil (977) (59ZPC(316)164). The structure was confirmed by at least four syntheses in the next few years. The most important involves a Shaw synthesis (Section 2.13.3.1.2e) of the acetal (975) and hydrolysis to the aldyhyde (976) followed by a Strecker reaction (potassium cyanide, ammonia and ammonium chloride) to give DL-willardiine (977) after resolution, the L-isomer was identical with natural material (62JCS583). Although not unambiguous, a Principal Synthesis from the ureido acid (978) and ethyl formylacetate is the most direct route (64ZOB407). 

Gmelin R. The free amino acids in the seeds of Acacia willardiana (Mimosa-ceae). Isolation of willardiin, a new plant amino acid which is probably L-beta-(3-uracil)-alpha-aminopropionic acid. Hoppe Seylers Z. Physiol. Chem. 1959 316 164— 169. 

Willardine is the (5)-a-amino acid l-/J-amino-)S-carboxyethyluracil (665). It was first isolated from the seeds of Acacia willardiana, and later from other species of Acacia <62JCS583>. Lathyrine (666) is another nonprotein a-amino acid, which was isolated from the seeds of Lathyrus tingitanus... 

Gmelin, R., and P. K. Hietala S-[p-Carboxy-isopropyl]-L-Cystein, eine neue Amino-saure aus den Samen von Acacia millefolia und Acacia willardiana (Mimosaceae). Hoppe-Seyler s Z. physiol. Chem. 322, 278 (1960). 

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