- Stereoselective synthesis of (3S,4S)-tert-butyl-N-Boc-3-ethyl-4-hydroxy-l- prolinate and (3S,4R)-tert-butyl-N-Boc-3-ethyl-4-hydroxy-l-prolinate
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Diastereomers of tert-butyl-N-Boc-3-ethyl-4-hydroxy-l-prolinate 1 and 2 have been synthesized in six steps starting from readily available Boc-protected trans-4-hydroxy-l-proline. The key reactions in the synthesis are asymmetric reductions, firstly on th
- Chabaud, Pauline,Pèpe, Gérard,Courcambeck, Jér?me,Camplo, Michel
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- Synthesis of 4-(Arylmethyl)proline Derivatives
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A synthesis of 4 - (arylmethyl)proline by using Suzuki cross-couplings was developed. The route permits access to a variety of 4-substituted proline derivatives bearing various aryl moieties that expand the toolbox of proline analogues for studies in chemistry and biology.
- Loosli, Simon,Foletti, Carlotta,Papmeyer, Marcus,Wennemers, Helma
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p. 508 - 510
(2019/02/26)
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- Synthesis method of teneligliptin-related impurity
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The invention discloses a synthesis method of a teneligliptin-related impurity, optimal reaction steps and reaction conditions are screened out through a large number of experiments, the whole processis reasonable in design, high in operability, mild in reaction condition and high in yield, and industrial production can be realized. According to the invention, Boc-L-hydroxyproline and 1-(3-methyl-1-phenyl-5-pyrazolyl)piperazine are taken as raw materials, and the raw materials are subjected to seven-step reaction to synthesize the teneligliptin-related impurity, and the prepared teneligliptin-related impurity is high in purity, can provide a basis for quality control, safety and efficiency evaluation of teneligliptin, and has important application values.
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- Synthesis technology of N-Boc-4-oxo-L-proline tert-butyl ester
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The invention discloses a synthesis technology of N-Boc-4-oxo-L-proline tert-butyl ester, and relates to the technical field of medicine synthesis. The synthesis technology solves the problems that inthe prior art, the production cost is low, the product yield is low, and the synthesis technology is not suitable for industrial production. According to the synthesis technology, Boc anhydride is used to generate tert-butyl carbonate, special esterification reagents namely O-tert-butyl-N,N'-diisopropyl isourea and EDC condensation reagent are not used, and the production cost is reduced by morethan 70%. Sodium hypochlorite is directly used to replace ruthenium tetroxide and chromium trioxide to prepare oxidized hydroxyl and is safe and reliable, furthermore, the post treatment is simple, the environmental pollution is greatly reduced, the operation of the synthesis technology is easy to perform, the technological conditions are easy to control, the synthesis technology is suitable for massive production, and the yield of step three can reach 69% and is higher than that of a conventional technology.
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- SYNTHETIC SPHINGOLIPID-LIKE MOLECULES, DRUGS, METHODS OF THEIR SYNTHESIS AND METHODS OF TREATMENT
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Small molecules comprised of azacyclic constrained sphingolipid-like compounds and methods of their synthesis are provided. Formulations and medicaments are also provided that are directed to the treatment of disease, such as, for example, neoplasms, canc
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- An Unconventional Redox Cross Claisen Condensation-Aromatization of 4-Hydroxyprolines with Ketones
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Reaction of α-amino acids, particularly prolines and their derivatives with carbonyl compounds via decarboxylative redox process, is a viable strategy for synthesis of structurally diverse nitrogen centered heterocyclics. In these processes, the decarboxylation is the essential driving force for the processes. The realization of the redox process without decarboxylation may offer an opportunity to explore new reactions. Herein, we report the discovery of an unprecedented redox Claisen-type condensation aromatization cascade reaction of 4-substituted 4-hydroxyproline and its esters with unreactive ketones. We found that the use of propionic acid as a catalyst and a co-solvent can change the reaction course. The commonly observed redox decarboxylation and aldol condensation reactions are significantly minimized. Moreover, unreactive ketones can effectively participate in the Claisen condensation reaction. The new reactivity enables a redox cyclization via an unconventional Claisen-type condensation reaction of in situ formed enamine intermediates from ketone precursors with 4-substituted 4-hydroxyproline and its esters as electrophilic acylation partners. Under the reaction conditions, the cascade process proceeds highly regio- and stereoselectively to afford highly synthetically and biologically valued cis-2,3-dihydro-1H-pyrrolizin-1-ones with a broad substrate scope in efficient 'one-pot' operation, whereas such structures generally require multiple steps.
- Tang, Mi,Sun, Rengwei,Li, Hao,Yu, Xinhong,Wang, Wei
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p. 8419 - 8425
(2017/08/23)
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- Substituted saturated aza heterocycles as inhibitors of nitric oxide synthase
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Disclosed herein are compounds of Formula (I) STR1 and pharmaceutically acceptable salts thereof which have been found useful in the treatment of nitric oxide synthase mediated diseases and disorders, including neurodegenerative disorders, disorders of ga
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- Synthesis of kainoid analogues
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4-oxoproline has been used as a chiral template in a synthesis of kainoid analogues which are epimeric with the parent compound at C-3.
- Barraclough, Paul,Hudhomme, Pietrick,Spray, Caroline A.,Young, Douglas W.
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p. 4195 - 4212
(2007/10/02)
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