52709-42-9Relevant academic research and scientific papers
Sequential Au/Cu Catalysis: A Two Catalyst One-Pot Protocol for the Enantioselective Synthesis of Oxazole α-Hydroxy Esters via Intramolecular Cyclization/Intermolecular Alder-Ene Reaction
Nalivela, Kumara Swamy,Rudolph, Matthias,Baeissa, Elham S.,Alhogbi, Basma G.,Mkhalid, Ibraheem A. I.,Hashmi, A. Stephen K.
supporting information, p. 2183 - 2190 (2018/04/30)
A convenient protocol for the enantioselective synthesis of oxazole α-hydroxy ester derivatives 4 from readily available propargylamides 1 and alkylglyoxylates 3 was developed. The first step of the one-pot procedure is the selective intramolecular in situ formation of an alkylideneoxazoline 2, which then in an intermolecular reaction is enantioselectively transformed to the oxazole α-hydroxy ester derivatives 4 in quantitative yield and good to excellent enantioselectivity via an asymmetric copper(II)-catalyzed Alder-ene reaction. (Figure presented.).
Asymmetric Catalytic Aza-Diels–Alder/Ring-Closing Cascade Reaction Forming Bicyclic Azaheterocycles by Trienamine Catalysis
Li, Yang,Barl?se, Casper,J?rgensen, Julie,Carlsen, Bj?rn Drei?,J?rgensen, Karl Anker
supporting information, p. 38 - 41 (2017/01/09)
An asymmetric catalytic aza-Diels–Alder/ring-closing cascade reaction between acylhydrazones and in situ formed trienamines is presented. The reaction proceeds through a formal aza-Diels–Alder cycloaddition, followed by a ring-closing reaction forming the hemiaminal ring leading to chiral bicyclic azaheterocycles in moderate to good yield (up to 71 %), good enantio- (up to 92 % ee) and diastereoselectivity (up to >20:1 d.r.). Furthermore, transformations are presented to show the potential application of the formed product.
POLYGLYOXYLATES, MANUFACTURE AND USE THEREOF
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Page/Page column 25, (2015/11/27)
Self-immolative polymers degrade by an end-to-end depolymerisation mechanism in response to the cleavage of a stabilizing end-cap from the polymer terminus. Examples include homopolymers, mixed polymers including block copolymers, suitable for a variety of applications. A polyglyoxylate can be end-capped or capped with a linker as in a block copolymer.
The catalytic synthesis of carboniolamide: The role of sp 3 hybridized oxygen
Zhang, Yi,Dai, Yuchi,Li, Guigen,Cheng, Xu
, p. 2644 - 2648 (2015/02/02)
A catalytic synthesis of carboniolamide has been reported. The strategy was straightforward with aldehyde and amide as starting materials. The products can be isolated as precipitates from the reaction mixture. The factor that stabilizes the labile functionality of hemiaminal was elucidated as a sp 3 hybridized oxygen.
The catalytic synthesis of carboniolamide: The role of sp 3 hybridized oxygen
Zhang, Yi,Dai, Yuchi,Li, Guigen,Cheng, Xu
, (2015/08/06)
A catalytic synthesis of carboniolamide has been reported. The strategy was straightforward with aldehyde and amide as starting materials. The products can be isolated as precipitates from the reaction mixture. The factor that stabilizes the labile functionality of hemiaminal was elucidated as a sp 3 hybridized oxygen.
Polyglyoxylates: A versatile class of triggerable self-immolative polymers from readily accessible monomers
Fan, Bo,Trant, John F.,Wong, Andrew D.,Gillies, Elizabeth R.
supporting information, p. 10116 - 10123 (2014/08/05)
Self-immolative polymers, which degrade by an end-to-end depolymerization mechanism in response to the cleavage of a stabilizing end-cap from the polymer terminus, are of increasing interest for a wide variety of applications ranging from sensors to controlled release. However, the preparation of these materials often requires expensive, multistep monomer syntheses, and the degradation products such as quinone methides or phthalaldehydes are potentially toxic to humans and the environment. We demonstrate here that polyglyxoylates can serve as a new and versatile class of self-immolative polymers. Polymerization of the commercially available monomer ethyl glyoxylate, followed by end-capping with a 6-nitroveratryl carbonate, provides a poly(ethyl glyoxylate) that depolymerizes selectively upon irradiation with UV light, ultimately generating ethanol and the metabolic intermediate glyoxylic acid hydrate. To access polyglyoxylates with different properties, the polymerization and end-capping approach can also be extended to other glyoxylate monomers including methyl glyoxylate, n-butyl glyoxylate, and benzyl glyoxylate, which can be easily prepared from their corresponding fumaric or maleic acid derivatives. Random copolymers of these monomers with ethyl glyoxylate can also be prepared. Furthermore, using a multifunctional end-cap that is UV-responsive and also enables the conjugation of another polymer block via an azide-alkyne "click" cycloaddition, amphiphilic self-immolative block copolymers are also prepared. These block copolymers self-assemble into micelles in aqueous solution, and their poly(ethyl glyoxylate) blocks rapidly depolymerize upon UV irradiation. Overall, these strategies are expected to greatly expand the utility of self-immolative polymers by providing access for the first time to self-immolative polymers with tunable properties that can be readily obtained from simple monomers and can be designed to depolymerize into nontoxic products.
Convenient synthesis of Nε-(carboxymethyl)lysine, a key advanced glycation endproduct biomarker
Andersen, Jeanette M.,Hjelmgaard, Thomas,Dragsted, Lars O.,Nielsen, John
scheme or table, p. 531 - 534 (2012/04/04)
Advanced glycation endproducts (AGEs) are formed when sugars react with peptides and proteins without the help of enzymes and by thermal processing of food such as baking and frying. AGEs and especially N-(carboxymethyl) lysine (CML) has been used as general key biomarkers for oxidative stress and a number of diseases associated with poor lifestyle. Herein we present the first synthetic pathway to the free zwitter ion of CML via a protected intermediate. Georg Thieme Verlag Stuttgart · New York.
Synthesis of hexa- and pentasubstituted diketopiperazines from sterically hindered amino acids
Brown, Zachary Z.,Schafmeister, Christian E.
supporting information; experimental part, p. 1436 - 1439 (2010/06/20)
Chemical equation presented Steric hindrance assists In the formation of hindered diketopiperazines using acyl-transfer coupling. In acyl-transfer coupling, the carboxylate of an unprotected N-alkylamino acid attacks an active ester to form a transient anhydride that undergoes an O,N acyl transfer to form a tertiary amide. If the active ester Is part of an N-alkylamino acid It will form a diketopiperazine. It is demonstrated here that acyl-transfer coupling can assemble highly functionalized bis-peptides bearing a functional group on every monomer.
Highly enantioselective organocatalytic Michael addition of nitroalkanes to 4-oxo-enoates
Lu, Hai-Hua,Wang, Xu-Fan,Yao, Chang-Jiang,Zhang, Jian-Ming,Wu, Hong,Xiao, Wen-Jing
supporting information; experimental part, p. 4251 - 4253 (2011/03/19)
A useful Michael addition reaction using nitroalkanes as the nucleophile and 4-oxo-enoates as the Michael acceptor has been disclosed, and the reaction allows expedient access to functionalized chiral γ-keto esters in high yields and excellent enantioselectivities (up to 98% ee), with a low catalyst loading.
SATURATED FUSED [1,2-B] PYRIDAZINONE COMPOUNDS
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, (2008/12/06)
The invention is directed to saturated fused [1,2-b]pyridazinone compounds and pharmaceutical compositions containing such compounds that are useful in treating infections by hepatitis C virus.
