By enzymatic hydrolysis of gaultherin (monotropitoside), primeverin, rhamnicoside and other glycosides: Goris, Vischniac, Compt. Rend. 169, 871 (1919); Bridel, ibid. 179, 991 (1924); Bridel, Charaux, ibid. 180, 857 (1925); Richter, J. Chem. Soc. 1936, 1701. Synthesis: Helferich, Rauch, Ber. 59, 2655 (1926); Ann. 455, 168 (1927); McCloskey, Coleman, J. Am. Chem. Soc. 65, 1778 (1943).