. . . "Preferably, reduction is carried out by use of a hydrogenating/reducing agent such as sodium borohydride, sodium triacetoxyborohydride, or sodium cyanoborohydride in a solvent, for example, water, an alcohol (e.g., methanol, ethanol, or isopropyl alcohol), an ether (e.g., tetrahydrofuran, dioxane, or diethyl ether), a halohydrocarbon (e.g., dichloromethane or chloroform), acetonitrile, or dimethyl" . . .