MEDV-13 for QSAR studies on the COX-2 inhibition by indomethacin amides and esters

A molecular electronegativity distance vector based on 13 atomic types (MED V-13), is a descriptor for predicting the biological activities of molecule s based on the quantitative structure-activity relationship (QSAR). The MED V-13 with 91 descriptors is employed to describe the structures of a series of selective cyclooxygenase-2 (COX-2) inhibitors including 16 indomethacin and its amide and ester derivatives (ImAE). A principal component regressi on (PCR) is used to derive a QSAR model relating the biological activities expressed by pIC(50) values to the MEDV-13. With the number of principal co mponents of 6, the correlation coefficient (R) and the root mean square err or (RUS) are 0.9245 and 0.1682 in modeling stage, and 0.8417 and 0.2389 in leave-one-out prediction step, respectively.