Structural Elucidation and Complete NMR Spectral Assignments of Monascus Monacolin Analogs

One new monacolin analog, monacolin V (1), together with two new monacolin-like natural products, 6-hydroxyl monacolin P (2) and 3-keto monacolin S (3), were isolated from the ethyl acetate portion of red yeast rice ethanol extract. Their structures were identified by HRESIMS and NMR experiments, and the complete assignments of ¹H and ¹³C NMR data for three compounds were obtained by the aid of HSQC, HMBC, ¹H-¹H COSY, and NOESY data. This is the first time that the NMR data of compounds 2 and 3 have been fully assigned.