127572-59-2Relevant academic research and scientific papers
One-pot synthesis of pyrroles using a titanium-catalyzed multicomponent coupling procedure
Pasko, Cody M.,Dissanayake, Amila A.,Billow, Brennan S.,Odom, Aaron L.
, p. 1168 - 1176 (2016/02/16)
A simple one-pot procedure for the production of 2-carboxylpyrroles with 4-alkyl, 5-alkyl, 4-aryl, 4-aryl-5-alkyl, or 3,4-diaryl substitution patterns is presented. The procedure involves the titanium-catalyzed multicomponent coupling of alkynes, primary amines and isonitriles to give 1,3-diimines in situ; the multicomponent product is then treated with the ethyl ester of glycine hydrochloride to give the NH-pyrrole. The reaction can be carried out with the neutralized glycine ester or with the hydrochloride salt using DBU as a base. Yields of pyrrole based on starting alkyne varied from 25 to 65% over the one pot procedure, and in most cases only one regioisomer of the product is observed. Further, it is proposed that the regioselectivities of the reactions are a result of rate-determining ring closure after relatively fast transimination with glycine ethyl ester.
Pyrrole-based antitubulin agents: Two distinct binding modalities are predicted for C-2 analogues in the colchicine site
Da, Chenxiao,Telang, Nakul,Barelli, Peter,Jia, Xin,Gupton, John T.,Mooberry, Susan L.,Kellogg, Glen E.
supporting information; scheme or table, p. 53 - 57 (2012/04/04)
3,5-Dibromo-4-(3,4-dimethoxyphenyl)-1H-pyrrole-2-carboxylic acid ethyl ester is a promising antitubulin lead agent that targets the colchicine site of tubulin. C-2 analogues were synthesized and tested for microtubule depolymerizing and antiproliferative activity. Molecular modeling studies using both GOLD docking and HINT (Hydropathic INTeraction) scoring revealed two distinct binding modes that explain the structure-activity relationships and are in accord with the structural basis of colchicine binding to tubulin. The binding mode of higher activity compounds is buried deeper in the site and overlaps well with rings A and C of colchicine, while the lower activity binding mode shows fewer critical contacts with tubulin. The model distinguishes highly active compounds from those with weaker activities and provides novel insights into the colchicine site and compound design.
A Modular Synthesis of the Lamellarins: Total Synthesis of Lamellarin G Trimethyl Ether
Handy, Scott T.,Zhang, Yanan,Bregman, Howard
, p. 2362 - 2366 (2007/10/03)
A modular synthesis of the lamellarin family of natural products has been developed that is based on the application of three iterative halogenation/cross-coupling reaction sequences. The ability to halogenate the pyrrole core in a regioselective fashion, even in the presence of highly electron-rich aryl substituents, has been established. The compatibility of Suzuki coupling conditions with free alcohols and phenols in the boronic acids has been employed to reduce the number of protection/deprotection steps. Indeed, the presence of a free phenol on boronic acid 3 has been determined to be critical for the successful final coupling in route to lamellarin G trimethyl ether, since protected versions fail to undergo coupling.
An unusual dehalogenation in the Suzuki coupling of 4-bromopyrrole-2-carboxylates
Handy, Scott T.,Bregman, Howard,Lewis, Jennifer,Zhang, Xiaolei,Zhang, Yanan
, p. 427 - 430 (2007/10/03)
An unusual dehalogenation of 4-bromopyrrole-2-carboxylates under Suzuki coupling conditions has been observed. This dehalogenation can be suppressed by protection of the pyrrole nitrogen. Using a BOC protecting group, not only is dehalogenation suppressed
Application of 2-Substituted Vinamidinium Salts to the Synthesis of 2,4-Disubstituted Pyrroles
Gupton, John T.,Krolikowski, Dale A.,Yu, Richard H.,Riesinger, Steve W.,Sikorski, James A.
, p. 4735 - 4740 (2007/10/02)
A variety of 2-substituted vinamidinium salts react with α-amino acid esters under basic conditions to produce 2-carbethoxy-4-substituted-pyrroles in good yield.The overall process represents a short and efficient synthesis of highly functionalized pyrrol
