enamines followed by ring cleavage yielded keto-enoic acids. The latter on Huang-Minlon reduction gave the enoic acids which on oxidation furnished the dioic acids. Ozonization of the enoic acids followed by sodium borohydride reduction of the ozonide yielded ω-hydroxy acids. The C16 and C15 dioic and ω-hydroxy acids, suitable for conversion to macrocyclic ketones and lactones, were thus prepared.