Abstract: A new, quite versatile, method for the synthesis of semicorrins is described which is based on the special utility of isoxazoles as intermediates. he model studies disclosed in the preceding Tpaper now allow us to more clearly define an actual corrin synthesis. Let us, therefore, refocus our attention on octamethylcorrin (1). In this connection mention should be made of the fact thit the details of corrin biosynthesis remain obscure. How-
![3-[3-(1,1-dimethyl-3-oxo-butyl)-isoxazol-5-yl]-2,2-dimethyl-propionitrile结构式](https://image.chemsrc.com/caspic/068/29945-91-3.png)