193274-08-7

Upstream product

• 1026087-20-6 3(R)-benzyloxy-2-(2-tert-butoxycarbonylamino-2-methyl-propionyl-amino)-propionic acid 
• 71760-04-8 propylphosphonic anhydride 
• 193274-04-3 3a-(R)-Benzyl-2-methyl-2,3a,4,5,6,7-hexahydro-pyrazolo[4,3-c]pyridin-3-one 
• 159634-89-6 (R)-3-Benzyloxy-2-(2-tert-butoxycarbonylamino-2-methyl-propionylamino)-propionic Acid 
• 193274-37-2 (R)-3a-benzyl-2-methyl-4,5,6,7-tetrahydro-2H-pyrazolo[4,3-c]pyridin-3(3aH)-one (2R,3R)-2,3-dihydroxysuccinate 
• 193274-00-9 3-(R,S)-Benzyl-4-oxo-piperidine-1,3-dicarboxylic acid 1-tert-butyl ester 3-methyl ester 
• 161491-24-3 methyl 1-tert-butoxycarbonyl-4-oxo-3-piperidinecarboxylate 
• 108554-34-3 methyl 4-oxonipecotate 
• 193274-02-1 2,3a,4,5,6,7-hexahydro-2-methyl-3-oxo-3a-(phenylmethyl)-5H-pyrazolo[4,3-c]pyridine-5-carboxylic acid 1,1-dimethylethyl ester 

Downstream Products

• 193273-66-4 capromorelin 

Relevant academic research and scientific papers

Practical synthesis of capromorelin, a growth hormone secretagogue, via a crystallization-induced dynamic resolution

A practical synthesis of capromorelin (1), a growth hormone secretagogue, is described that utilizes as a key step a crystallization-induced dynamic resolution (CIDR) of (±)-3a-benzyl-2-methyl-4,5,6,7-tetrahydro-2H-pyrazolo[4,3-c]pyridin-3(3aH)-one [(±)-2] by L-tartaric acid salt formation, yielding (R)-2.L-tartaric acid in high chemical yield (>85%) and with diastereomeric excess (de) of ～98%. Treatment of (R)-2.L-tartaric acid with ammonium hydroxide provided (R)-2 without loss of chiral purity. In situ generated (R)-2 was coupled with (R)-3-(benzyloxy)-2-(2-(tert-butoxycarbonyl)-2-methylpropanamido)propanoic acid [(R)-3] to give predominantly a single diastereomer of N-Boc-protected capromorelin [(1R,3aR)-4]. This process was used to prepare bulk quantities of capromorelin from (±)-2 to support preclinical toxicology studies.

Pyrazolinone-piperidine dipeptide growth hormone secretagogues (GHSs): Discovery of capromorelin

Novel pyrazolinone-piperidine dipeptide derivatives were synthesized and evaluated as growth hormone secretagogues (GHSs). Two analogues, capromorelin (5, CP-424391-18, hGHS-R1a Ki=7 nM, rat pituicyte EC50=3 nM) and the des-methyl an

Process for preparing growth hormone secretagogues

This invention relates to improved processes for preparing compounds of Formula II, and compounds of Formula III, wherein R1, R2, R3 and Prt are defined as set forth in the specification.