2,2,2-Triphenyl-2λ5-3-oxa-2-phosphabicyclo[3.1.0]hexane is an intermediate in synthesizing α-(Methylenecyclopropyl)glycine (M303150), a homolog of Hypoglycine A (H998400), is an unusual amino acid found in Litchi chinensis seeds and is shown to have antimutagenic activity against spontaneous mutation of Salmonella typhimurium TA.