119139-23-0, In heterogeneous catalysis, the catalyst is in a different phase from the reactants. At least one of the reactants interacts with the solid surface in a physical process called adsorption in such a way. 119139-23-0, name is 3,4-Di(1H-indol-3-yl)-1H-pyrrole-2,5-dione. In an article£¬Which mentioned a new discovery about 119139-23-0
Total Synthesis of Cryptophycins-1, -3, -4, -24 (Arenastatin A), and -29, Cytotoxic Depsipeptides from Cyanobacteria of the Nostocaceae
A convergent synthesis of cryptophycins has been developed in which (5S,6R)-5-hydroxy-6-methyl-8-phenylocta-2(E),7(E)-dienoic acid (A) is coupled with an amino acid segment (B). Two stereo-selective routes to A are described, the first employing allylation of an alpha-homochiral aldehyde and the second using asymmetric crotylation of an achiral aldehyde to establish the two stereogenic centers present in A. The styryl moiety of A was attached either via Stille coupling or through a Wadsworth-Emmons condensation with diethyl benzylphosphonate. The amino acid subunit B was prepared from benzyl (2S)-2-hydroxyisocaproate by connection first to AT-Boc-beta-alanine or its (2R)-methyl-substituted derivative and then to (2R)-N-Boc-O-methyltyrosine or its m-chloro derivative. Fusion of the A and B subunits was accomplished by initial esterification of the former with the latter, followed by macrocyclization using diphenyl phosphorazidate. In this way, cryptophycin-3, -4, and -29 were obtained along with the nonnatural cyclic depsipeptide 52. Epoxidation of cryptophycin-3 with dimethyldioxirane gave cryptophycin-1; analogous epoxidation of 52 afforded arenastatin A (cryptophycin-24).
The proportionality constant is the rate constant for the particular unimolecular reaction. the reaction rate is directly proportional to the concentration of the reactant. I hope my blog about 119139-23-0 is helpful to your research. 119139-23-0
Reference£º
Chiral nitrogen ligands in late transition metal-catalysed asymmetric synthesis¡ªI. Addressing the problem of ligand lability in rhodium-catalysed hydrosilations,
Nitrogen-Containing Ligands for Asymmetric Homogeneous and Heterogeneous Catalysis