Basic substances isolated from the bark ofNaucleadiderrichiiand not placed in one of the three earlier alkaloidal categories include an alkaloid, C21H26N2O4, designated ND-370, and an amorphous material that appears to be an alkaloidal glycoside. Also isolated were the non-basic substances benzamide and antiarol (3,4,5-trimethoxyphenol), and two monoterpenoids given the names naucleol and naucledal; the spectroscopic characteristics of naucleol, C9H14O3, can be accounted for by structure1a, and those of naucledal, C10H12O4, by structure2a, but the data do not establish the structures unequivocally. The structural relationships between the various constituents isolated from this plant and their possible biogenetic implications are discussed.