167904-79-2

Upstream product

• 81167-39-7 methyl N-(diphenylmethylene)glycinate 
• 106-96-7 propargyl bromide 
• 67-56-1 methanol 
• 173201-94-0 methyl N-(diphenylmethyl)iminoacetate 
• 91-00-9 Benzhydrylamine 
• 1013-88-3 Benzophenone imine 
• 119-61-9 benzophenone 

Downstream Products

• 118169-12-3 Methyl 2-(benzhydrylideneamino)-4-pentenoate 
• 167904-81-6 methyl (2RS,4E)-2-[N-(diphenylmethylidene)amino]-5-(tributylstannyl)but-4-enoate 
• 1610943-91-3 C₃₁H₄₅NO₂Sn 
• 951127-25-6 N-[(2R,3S)-2-(2,5-difluorophenyl)tetrahydro-5-oxo-2H-pyran-3-yl]carbamic acid 1,1-dimethylethyl ester 
• 1172623-95-8 (±)-tert-butyl (1-(methoxy(methyl)amino)-1-oxopent-4-yn-2-yl)carbamate 
• 1172623-96-9 (±)-tert-butyl (1-(2,5-difluorophenyl)-1-oxopent-4-yn-2-yl)carbamate 
• 1172623-98-1 tert-butyl [(2R,3S)-2-(2,5-difluorophenyl)-3,4-dihydro-2H-pyran-3-yl]carbamate 
• 1172623-99-2 tert-butyl [(2R,3S)-2-(2,5-difluorophenyl)-5-hydroxytetrahydro-2H-pyran-3-yl]carbamate 
• 167904-80-5 methyl (R,S)-2-[N-(diphenylmethylidene)amino]-4-(tributylstannyl)but-4-enoate 
• 216988-58-8 methyl 4-iodo-5-(2-thienyl)-1-(4-tolylsulfonyl)-2,3-dihydropyrrole-2-carboxylate 

Relevant academic research and scientific papers

Surface-enhanced Raman scattering of alkyne-conjugated MoS2: A comparative study between metallic and semiconductor phases

Raman enhancement on nonmetallic flat two-dimensional (2D) nanomaterial surfaces has attracted a great deal of attention since the discovery of graphene-enhanced Raman scattering. Molybdenum disulfide (MoS2) is a flat 2D nanomaterial with unique electronic and physical properties that can be applied in surface-enhanced Raman spectroscopy (SERS). Herein, we report a lithium-exfoliated MoS2 (Li-MoS2) has a metallic phase content of about 70%, which is three times higher than the metallic phase content of 20% in thioglycolic acid-exfoliated MoS2 (T-MoS2). Li-MoS2 therefore displays a 2-3 fold increase in the Raman signal for rhodamine 6G (R6G) used as an analyte. Furthermore, the conjugation of a thiol-terminated alkyne with Li-MoS2 also provided a greater SERS signal at 2123 cm-1 than that of T-MoS2. A defect-rich metallic MoS2 monolayer can therefore be used as the perfect substrate for surface-enhanced Raman scattering, although pristine MoS2 hardly exhibits an SERS effect. This study proved that (1) defect-rich metallic MoS2, (2) dipole-dipole interactions, and (3) the enhanced charge transfer effect of MoS2 monolayers are the three primary and essential parameters for enhancing the Raman signals of analytes on MoS2. Key observations include the fact that some alkyne groups were directly coordinated to the edges of Li-MoS2 defect sites, which shifted the alkyne signal to 2153 cm-1 in alkyne spectral mapping. More importantly, to quantify the SERS performance of Li-MoS2, SERS imaging of live cells was demonstrated using the unique alkyne signal at 2123 cm-1.

Enantioenriched α-substituted glutamates/pyroglutamates via enantioselective cyclopropenimine-catalyzed Michael addition of amino ester imines

A procedure for the enantioselective synthesis of α-substituted glutamates and pyroglutamates via a cyclopropenimine-catalyzed Michael addition of amino ester imines is described. Enantioselectivities of up to 94% have been achieved, and a variety of functional groups were found to be compatible. The impact of the catalyst structure and imine substitution is discussed. Compared to other methods, this protocol allows for a broader and more enantioselective access to pyroglutamate derivatives.

SUBSTITUTED AMINO SIX-MEMBERED SATURATED HETEROCYCLIC FAT USED AS LONG-ACTING DPP-IV INHIBITOR

The present application relates to a substituted amino six-membered saturated heteroalicycle represented by formula I as a long-acting DPP-IV inhibitor, a method for preparing the same, a pharmaceutical composition comprising the same, and a use of the same in treating and/or preventing diseases and disorders benefitting from DPP-IV inhibition.

Rhodium(I)-catalyzed cycloisomerization reaction of yne-allenamides: An approach to cyclic enamides

In this paper, we demonstrate a successful conversion of alkynyl allenamides to triene-containing heterocycles via a rhodium(I)-catalyzed cycloisomerization reaction. Georg Thieme Verlag Stuttgart.

A new method for the preparation of functionalized unnatural α-H-α-amino acid derivatives

A new method for the preparation of α-H-α-amino acids is reported based on the α-alkylation of iminoacetic acid esters or amides. These imines are readily available by the reaction of glyoxylic acid esters with branched primary amines. The subsequent reaction with methanolic ammonia gave the corresponding iminoacetic acid amides. α-Alkylation of these imines with various electrophiles under basic conditions, followed by an acidic hydrolysis, gave α-amino acids, esters, or amides in up to 93% yield. α-Alkylation under chiral PTC conditions resulted in mono-alkylated amino acids with 90% ee.

Synthesis of highly functionalized phenylalanine derivatives via cross-enyne metathesis reactions

A new method for the synthesis of constrained phenylalanine derivatives is described. In this regard, the simple synthesis of acyclic diene building blocks embodying an α-amino acid moiety has been achieved. The diene building blocks have been prepared by cross enyne-metathesis reaction as a key step. The Diels-Alder reaction of the dienes with a dienophile such as dimethyl acetylenedicarboxilate (DMAD) followed by oxidation of the resulting cycloadduct gave highly substituted phenylalanine derivatives.

An approach to 2,3-dihydropyrroles and β-iodopyrroles based on 5-endo-dig cyclisations

A representative series of homopropargylic sulfonamides 19 and 22b have been found to undergo smooth 5-endo-dig cyclisation upon exposure to excess iodine in acetonitrile containing potassium carbonate. The resulting 4-iodo-2,3-dihydropyrroles 23 readily react with two equivalents of DBU in DMF at 20°C to give the corresponding β-iodopyrroles 24 and 26 in excellent yields by the elimination of toluene-p-sulfinic acid. Use of less than two equivalents of base results in some loss of iodine. The iodo-2,3-dihydropyrroles 23 can be used in palladium-catalysed coupling reactions as shown by the efficient formation of the Sonogashira product 29 under mild conditions.

A Biocatalytic Route to Enantiomerically Pure Unsaturated α-H-α-Amino Acids

A set of both enantiomeric forms of non-proteinogenic, unsaturated α-H-α-amino acids was efficiently synthesized using a biocatalytic pathway. This route involved the straightforward synthesis of the required unsaturated amino acid amides, followed by resolution with an aminopeptidase present in Pseudomonas putida ATCC 12633 and/or a genetically modified organism, leading to the (S)-acids and (R)-amides. Undesired amino acid racemase activity was identified in the wild-type strain, which was absent in the newly developed organism. The (R)-amides were hydrolyzed under mild conditions using an amidase present in whole cells from Rhodococcus erythropolis NCIMB 11540 to the (R)-acids. The viability of this procedure was demonstrated with the multi-gram synthesis of a variety of unsaturated amino acids in excellent enantiopurity.

Synthesis of unusual α-amino acid derivatives via cross-enyne metathesis reaction

Various highly functionalized phenylalanine derivatives are prepared via cross-enyne metathesis and Diels-Alder reaction as key steps.

Polyethylene glycol (PEG) as polymeric support and phase-transfer catalyst in the soluble polymer liquid phase synthesis of α-amino esters

α-Substituted α-amino esters were synthesized in liquid-phase by polyethylene glycol (PEG) promoted alkylation of a polyethylene glycol-supported Schiff base activated glycine ester.