Pharmacaphores

In a study of possible drugs to treat cocaine abuse, the pharmacaphore shown in Figure 2.3 was obtained. 

A pharmacaphore model derived from cocaine and its analogues. 

A pharmacaphore gives some insight into the nature of the active site if we assume that all the active molecules bind at the same site. The accessible volume of the binding site can be estimated by taking the minimum volume required to enclose the complete set of superimposed active molecules. The binding site is presumed also to contain groups that interact with the elements of the pharmacaphore in a geometrical relationship that will match the pharmacaphore. 

Pharmacaphoric Pattern Matching in Files of Three-Dimensional Chemical Structures Comparison of Conformational-Searching Algorithms for Flexible Molecules. 

Scheme 48 Synthesis of a lactame pharmacaphore (Bristol-Meyers Squibb)...

After this success, Ir catalysts were employed more often, and it was shown that besides imines, C=0 as well as C=C btmds could be hydrogenated with good success. The hydrogenation depicted in Scheme 47 was developed by Lonza [38] for an intermediate of dextromethorphan and carried out on >100-kg scale. Important success factors were the ligand fine tuning and the use of a biphasic system. Chemoselectivity is high but catalyst productivity rather low for an economical technical application. Bristol-Meyers Squibb [111] achieved the first case of Ir diphosphine-catalyzed hydrogenation of a C=C bond to prepare a lactam pharmacaphore on a 20-kg scale (Scheme 48). DSM [112] in collaboration with Solvias developed a new route for biotin, based on the unprecedented reduction of... 

---