Classical QSAR began almost 30 years ago. This article briefly traces its development, use and impact in relation to drug design and medicinal chemistry. Particular aspects discussed include hydrophobicity, relative potency in a series, tissue selectivity, central nervous system penetration, pharmacokinetics, potency optimization, bioisosterism, mechanistic insights, synthesis termination, rece...

The relative potency of lignocaine, bupivacaine and etidocaine was estimated by forearm skin weals in four volunteers. Potency was estimated as the time to half-recovery of a sharp sensation in response to a needle-prick. The increase in duration of action with increased concentration was greater for bupivacaine and etidocaine as compared with lignocaine. At the same concentrations, bupivacaine...