Process research and development for a tetrazole-based growth hormone secretagogue (GHS) pharmaceutical development candidate.

BMS-317180 (1) is a potent, orally active agonist of the human growth hormone secretagogue (GHS) receptor. This manuscript details the process research and development efforts that enabled the synthesis of the phosphate salt of 1 on a multi-kilogram scale. Key considerations in the development of this process focused on safe execution and the requirement for telescoped synthetic transformations (i.

A preparatively convenient ligand-free catalytic PEG 2000 Suzuki-Miyaura coupling.

A ligand-free Suzuki-Miyaura reaction for the cross-coupling of aryl and heteroaryl bromides with aryl and heteroarylboronic acids has been developed utilizing catalytic polyethylene glycol 2000 (PEG 2000). This preparatively convenient system afforded the corresponding cross-coupled products in good to excellent isolated yields after a simple aqueous workup. Transmission electron microscopy (TEM) analysis of the Pd-PEG 2000 catalyst system revealed in situ-generated palladium nanoparticles after only 1 min of reaction.

Practical enantioselective synthesis of beta-substituted-beta-amino esters.

[reaction: see text] A practical, large-scale synthesis of a beta-amino ester 1 was developed. A chiral imine derived from (S)-phenylglycinol and 3-trimethylsilylpropanal was coupled with the Reformatsky reagent 3 with high diastereoselectivity (de > 98%) to give (SS)-4a as the major isomer. The amino alcohol residue of the coupling product 4 was oxidatively cleaved with sodium periodate in the presence of methylamine.

N-Amination of pyrrole and indole heterocycles with monochloramine (NH2Cl).

A survey of several electrophilic ammonia reagents for the N-amination of indole- and pyrrole-containing heterocycles revealed that monochloramine (NH(2)Cl) is an excellent reagent for this transformation. Pyrroles and indoles containing a variety of substitution were aminated on nitrogen with isolated yields ranging from 45% to 97%.