QSAR & QSPR

Constitutional descriptors• number of atoms• absolute and relative numbers of C, H, O, S, N, F, Cl, Br, I, Patoms• number of bonds (single, double, triple and aromatic bonds)• number of benzene rings, number of benzene rings divided by thenumber of atoms• molecular weight and average atomic weight• Number of rotatable bonds (All terminal H atoms are ignored)• Hbond acceptor - Number of hydrogen bond acceptors• Hbond donor - Number of hydrogen bond donorsThese simple descriptors reflect only the molecular composition of thecompound without using the geometry or electronic structure ofthe molecule.