lorobutoxy and the like; an alkoxy group of not more than 10 carbon atoms substituted with an alkoxy group of not more than 10 carbon atoms, e.g., 2-methoxyethoxy, 2-ethoxyethoxy and the like; an alkenyloxy group containing not more than 10 carbon atoms, e.g. allyloxy, 2-butenyloxy and the like; or an aralkyloxy group containing not more than 15 carbon atoms, e.g., benzyloxy, phenethyloxy, 1-pheny