7a-methyltetrahydropyrrolo[2,1-b][1,3]oxazol-5(6H)-one InChI=1/C7H11NO2/c1-7-3-2-6(9)8(7)4-5-10-7/h2-5H2,1H pyrrolo[2,1-b]oxazol-5(6H)-one, tetrahydro-7a-methyl-