154457-63-3

Upstream product

• 27784-76-5 tert-butyl diethylphosphonoacetate 
• 122-78-1 phenylacetaldehyde 
• 300-57-2 allylbenzene 
• 1663-39-4 tert-Butyl acrylate 
• 4489-84-3 3-methyl-1-phenylbut-2-ene 
• 86302-43-4 (tert-Butoxycarbonylmethylene)triphenylphosphorane 

Relevant academic research and scientific papers

Diastereoselective Radical Couplings Enable the Asymmetric Synthesis of anti-β-Amino-α-hydroxy Carboxylic Acid Derivatives

anti-β-Amino-α-(aminoxy) esters or amides are synthesized by merging polar asymmetric aza-Michael additions of lithium 1-phenylethylamides to α,β-unsaturated carboxylic acid derivatives and diastereoselective radical couplings with the persistent free rad

Asymmetric Syntheses of (+)-Preussin B, the C(2)-Epimer of (-)-Preussin B, and 3-Deoxy-(+)-preussin B

Efficient de novo asymmetric syntheses of (+)-preussin B, the C(2)-epimer of (-)-preussin B, and 3-deoxy-(+)-preussin B have been developed, using the diastereoselective conjugate addition of lithium (S)-N-benzyl-N-(α-methylbenzyl)amide to tert-butyl 4-phenylbut-2-enoate and diastereoselective reductive cyclizations of β-amino ketones as the key steps to set the stereochemistry. Conjugate addition followed by enolate protonation generated the corresponding β-amino ester. Homologation using the ester functionality as a synthetic handle gave the corresponding β-amino ketone. Hydrogenolytic N-debenzylation was accompanied by diastereoselective reductive cyclization in situ; reductive N-methylation then gave 3-deoxy-(+)-preussin B as the major diastereoisomeric product. Meanwhile, the same conjugate addition but followed by enolate oxidation with (+)-camphorsulfonyloxaziridine gave the corresponding anti-α-hydroxy-β-amino ester. α-Epimerization by oxidation and diastereoselective reduction then gave access to the corresponding syn-α-hydroxy-β-amino ester. Homologation of both of these diastereoisomeric α-hydroxy-β-amino esters gave the corresponding β-hydroxy-β-amino ketones. N-Debenzylation and concomitant diastereoselective reductive cyclization, followed by reductive N-methylation, provided the C(2)-epimer of (-)-preussin B and (+)-preussin B as the major diastereoisomeric products, respectively. The overall yields (from phenylacetaldehyde) were 19% for 3-deoxy-(+)-preussin B over seven steps, 8% for the C(2)-epimer of (-)-preussin B over nine steps, and 7% for (+)-preussin B over eleven steps.

Visible-Light-Controlled Ruthenium-Catalyzed Olefin Metathesis

Olefin metathesis is now one of the most efficient ways to create new carbon-carbon bonds. While most efforts focused on the development of ever-more efficient catalysts, a particular attention has recently been devoted to developing latent metathesis cat

Visible-Light-Controlled Ruthenium-Catalyzed Olefin Metathesis

Olefin metathesis is now one of the most efficient ways to create new carbon-carbon bonds. While most efforts focused on the development of ever-more efficient catalysts, a particular attention has recently been devoted to developing latent metathesis cat

Chiral integrated catalysts composed of bifunctional thiourea and arylboronic acid: Asymmetric aza-Michael addition of α,β-unsaturated carboxylic acids

The first intermolecular asymmetric Michael addition of nitrogen-nucleophiles to α,β-unsaturated carboxylic acids was achieved through a new type of arylboronic acid equipped with chiral aminothiourea. The use of BnONH2 as a nucleophile gives a range of enantioenriched β-(benzyloxy)amino acid derivatives in good yields and with high enantioselectivity (up to 90% yield, 97% enantiomeric excess (ee)). The obtained products are efficiently converted to optically active β-amino acid and 1,2-diamine derivatives.

Manipulating micellar environments for enhancing transition metal-catalyzed cross-couplings in water at room temperature

The remarkable effects of added salts on the properties of aqueous micelles derived from the amphiphile PTS are described. Most notably, Heck reactions run in the presence of NaCl lead to couplings on aryl bromides in water at room temperature. Olefin cross- and ring-closing metathesis reactions run in the presence of small amounts of pH-lowering KHSO4 are also accelerated, another phenomenon that does not apply to typical processes in organic media. These salt effects allow, in general, for synthetically valuable C-C bond-forming processes to be conducted under environmentally benign conditions. Recycling of the surfactant is also demonstrated.

Highly (E)-selective wadsworth-emmons reactions promoted by methylmagnesium bromide

(Chemical Equation Presented) An experimentally simple protocol for the very highly (E)-selective Wadsworth-Emmons reaction [(E):(Z) selectivities in excess of 180:1 in some cases] of a range of straight-chain and branched aliphatic, substituted aromatic, and base-sensitive aldehydes via reaction with an alkyl diethylphosphonoacetate and MeMgBr is reported.

Olefin cross-metathesis reactions at room temperature using the nonionic amphiphile "PTS": Just add water

(Chemical Equation Presented) The first examples of unsymmetrical olefin cross-metathesis reactions in water, involving water-insoluble substrates, at room temperature and using commercially available catalysts are reported. The key to success is to include small percentages of the nonionic, vitamin E-based amphiphile "PTS". The nanometer micelles formed accommodate water-insoluble substrates, along with a readily available Ru-based metathesis catalyst. Reactions proceed at ambient temperatures with high efficiency and very high E-selectivity, and products are easily isolated.

Substituted (aryl, heteroaryl, arylmethyl or heteroarylmethyl) hydroxamic acid compounds

This invention is directed to compounds of formula I: wherein the variables are as described herein. Compounds within the scope of the present invention possess useful properties, more particularly pharmaceutical properties. They are especially useful for inhibiting the production or physiological effects of TNF in the treatment of a patient suffering from a disease state associated with a physiologically detrimental excess of tumor necrosis factor (TNF). Compounds within the scope of the present invention also inhibit cyclic AMP phosphodiesterase, and are useful in treating a disease state associated with pathological conditions that are modulated by inhibiting cyclic AMP phosphodiesterase, such disease states including inflammatory and autoimmune diseases, in particular type IV cyclic AMP phosphodiesterase. Compounds within the scope of the present invention may also inhibit an MMP, and are useful in treating a disease state associated with pathological conditions that are modulated by inhibiting MMPs, such disease states involve tissue breakdown and those associated with a physiologically detrimental excess of TNF. The present invention is therefore also directed to the pharmaceutical use of the compounds, pharmaceutical compositions containing the compounds, intermediates leading thereto and methods for the preparation of the compounds and their intermediates.