74999-36-3Relevant academic research and scientific papers
ANTIVIRAL 1,3-DI-OXO-INDENE COMPOUNDS
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Paragraph 0415, (2021/10/22)
The invention provides compounds of Formula (I): as described herein, along with pharmaceutically acceptable salts, pharmaceutical compositions containing such compounds, and methods to use these compounds, salts and compositions for treating viral infections.
Synthesis and transformations of 5-chloro-2,2′-dipyrrins and their boron complexes, 8-chloro-BODIPYs
Wang, Haijun,Vicente, M. Graca H.,Fronczek, Frank R.,Smith, Kevin M.
, p. 5064 - 5074 (2014/05/06)
Symmetric dipyrrylketones 1a,b were synthesized in two steps from the corresponding α-free pyrroles, by reaction with thiophosgene followed by oxidative hydrolysis under basic conditions. The dipyrrylketones produced the corresponding 5-chloro-dipyrrinium salts or 5-ethoxy-dipyrrins on reaction with phosgene or Meerwein's salt, respectively. Boron complexation of the dipyrrins afforded the corresponding 8-functionalized BODIPYs (borondipyrromethenes) in high yields. The 5-chloro-dipyrrinium salts reacted with methoxide or ethoxide ions to produce monopyrrole esters, presumably via a 5,5-dialkoxy-dipyrromethane intermediate. In contrast, 8-chloro-BODIPYs underwent a variety of nucleophilic substitutions of the chloro group in the presence of alkoxide ions, Grignard reagents, and thiols. In the presence of excess alkoxide or Grignard reagent, at room temperature or above, substitution at the boron center also occurred. The 8-chloro-BODIPY was a particularly useful reagent for the preparation of 8-aryl-, 8-alkyl-, and 8-vinyl-substituted BODIPYs in very high yields, using Pd0-catalyzed Stille cross-coupling reactions. The X-ray structures of eleven BODIPYs and two pyrroles are presented, and the spectroscopic properties of the synthesized BODIPYs are discussed.
13C-labeled bilirubin: Synthesis of 31(3 2),171(172)-di-[13C]-mesobilirubin- XIIIα
Boiadjiev, Stefan E.,Lightner, David A.
scheme or table, p. 111 - 119 (2010/06/20)
The title compound, labeled with 13C in the ethyl groups was synthesized from K13CN and low-molecular-weight components. The synthetic relay compound was 31(32)[13C]- xanthobilirubinic acid methyl ester in a synthetic route that leads to a label in the ethyl β-substituent of a dipyrrinone model for bilirubin. This labeled dipyrrinone was oxidatively coupled to the dimethyl ester of mesobiliverdin-XIIIα, thereby providing a route to a 13C- labeled mesobiliverdin and mesobilirubin, with one carbon of each ethyl being 98% 13C-enriched.
Atropisomerism in monopyrroles
Boiadjiev, Stefan E.,Lightner, David A.
, p. 1721 - 1732 (2007/10/03)
As observed by NMR, iodopyrroles 1a and 1b (ethyl and methyl 3,5-dimethyl-4-[(1′-iodo-2′,2′-dimethyl)propyl]pyrrole-2- carboxylate) and a variety of related derivatives with iodine replaced by methoxy 2, thiomethyl 3, acetic acid esters 4, propionic acid ester 5 or malonic esters 6 exhibit restricted rotation about the C(4)-C(1′) bond due to the bulky tert-butyl group and an ortho effect from the sterically crowded 3,5-dimethylpyrrole. Most of the compounds, which are members of the rare class of atropisomers due to restricted rotation about an sp3-sp2 C-C bond, undergo diastereomeric enrichment by preparative TLC and crystallization. From dynamic NMR studies of the enriched diastereomers one can determine kinetic and thermodynamic parameters associated with the atropisomerism, e.g., ΔG? ～24 kcal/mol for 1 and 5 (313 K), ～22 kcal/mol for 3 (273 K), and ～25 kcal/mol for 6 (313 K) in C2D2Cl4 solvent.
Synthesis of cyanopyrroles
Cheng, Lingjiang,Lightner, David A.
, p. 46 - 48 (2007/10/03)
Regioselective synthesis of α-cyanopyrroles (vs. α- alkoxycarbonylpyrroles) using oximinocyanoacetate esters in a Knorr-type reductive condensation with β-diketones can be directed by the presence of water. Thus, methyl oximinocyanoacetate was reacted with pentane-2,4-dione in hot acetic acid in the presence of zinc dust to give exclusively 3,5- dimethylpyrrole-2-carbonitrile when the acetic acid was wet; whereas, in glacial acetic acid only methyl 3,5-dimethylpyrrole-2-carboxylate was isolated (~40% yield).
