Disclosed are compounds, compositions and methods for treating various diseases, syndromes, conditions and disorders, including pain. Such compounds are represented by Formula (I) as follows:
wherein A, L, R
1
, R
2
, R
4
and R
5
are defined herein.
Rh(II)/Brønsted Acid Catalyzed General and Highly Diastereo- and Enantioselective Propargylation of <i>in Situ</i> Generated Oxonium Ylides and C-Alkynyl N-Boc N,O-Acetals: Synthesis of Polyfunctional Propargylamines
The first metal/organo cooperatively catalyzed asymmetric reaction of C-alkynyl N-Boc-protected N,O-acetals with in situ generated oxonium ylides has been developed. This new type of propargylation allows for the efficient synthesis of structurally diverse unreported chiral propargylamines bearing oxa-quaternary stereocenters. The reaction features unprecedented substrate scope and high diastereo-
Acid treatment of alpha-hydroxy acetals induced 1,2-alkyl, aryl, or alkenyl migration. An alkenyl migration product was utilized as a starting material of methyl L-mycaroside synthesis.