- cis-4-Alkoxydialkyl- and cis-4-Alkoxydiarylprolinol Organocatalysts: High Throughput Experimentation (HTE)-Based and Design of Experiments (DoE)-Guided Development of a Highly Enantioselective aza-Michael Addition of Cyclic Imides to α,β-Unsaturated Aldehydes
-
A diverse family (37 compounds) of cis-4-alkoxydiorganylprolinol derivatives has been prepared and evaluated in organocatalysis for the first time. The combined use of high throughput experimentation (HTE) techniques with efficient analytical methods has led to the identification of two superior catalysts for the enantioselective addition of succinimide to α,β-unsaturated aldehydes. Further optimization of the reaction conditions with design of experiments (DoE) techniques established the catalyst of choice for the considered aza-Michael reaction, the corresponding adducts (12 examples) being obtained in good yields and excellent enantioselectivities (succinimide and maleimide donors). The synthetic versatility of these Michael adducts is illustrated by a two-step sequence leading to enantiopure 1,3-amino alcohols. (Figure presented.).
- Arenas, Ismael,Ferrali, Alessandro,Rodríguez-Escrich, Carles,Bravo, Fernando,Pericàs, Miquel A.
-
supporting information
p. 2414 - 2424
(2017/07/22)
-
- PHENYL AMINO PYRIMIDINE BICYCLIC COMPOUNDS AND USES THEREOF
-
The present invention relates to phenyl amino pyrimidine bicyclic compounds formula (I) which are inhibitors of protein kinases including JAK kinases. In particular the compounds are active against JAK1, JAK2, JAK3 and TYK2 kinases. The kinase inhibitors can be used in the treatment of kinase associated diseases such as immunological and inflammatory diseases including organ transplants; hyperproliferative diseases including cancer and myeloproliferative diseases; viral diseases; metabolic diseases; and vascular diseases.
- -
-
Page/Page column 63
(2014/01/17)
-
- Synthesis of a histamine H3 receptor antagonist - Manipulation of hydroxyproline stereochemistry, desymmetrization of homopiperazine, and nonextractive sodium triacetoxyborohydride reaction workup
-
(Figure presented) We have recently completed the synthesis of 1-[2-(4-cyclobutyl-[1,4]diazepane-1-carbonyl)-4-(3-fluoro-phenoxy) -pyrrolidin-1-yl]-ethanone, a hydroxyproline-based H3 receptor antagonist, on 100 g scale. The synthesis proceeds through four steps and route selection was driven by a desire to minimize the cost-of-goods. Naturally occurring trans-4-hydroxy-L-proline was chosen as the precursor to the targets core, which necessitated an inversion at both stereogenic centers. The inversions were accomplished through strategic employment of La Rosas lactone and a late-stage Mitsunobu reaction. A first generation synthesis that employed N-Boc-homopiperazine was improved in a second generation approach wherein homopiperazine was directly desymmetrized. Finally, the water solubility of a key intermediate necessitated the development of a nonextractive workup for the sodium triacetoxyborohydride reduction.
- Pippel, Daniel J.,Young, Lana K.,Letavic, Michael A.,Ly, Kiev S.,Naderi, Bita,Soyode-Johnson, Aki,Stocking, Emily M.,Carruthers, Nicholas I.,Mani, Neelakandha S.
-
experimental part
p. 4463 - 4471
(2010/10/02)
-
- SUBSTITUTED PYRROLIDINE AMIDES AS MODULATORS OF THE HISTAMINE H3 RECEPTOR
-
Certain substituted pyrrolidine amide compounds are histamine H3 receptor modulators useful in the treatment of histamine H3 receptor-mediated diseases.
- -
-
-
- Practical syntheses of 4-fluoroprolines
-
4-Fluoroprolines are among the most useful nonnatural amino acids in chemical biology. Here, practical routes are reported for the synthesis of the 2S,4R, 2S,4S, and 2R,4S diastereomers of 4-fluoroproline. Each route starts with (2S,4R)-4-hydroxyproline, which is a prevalent component of collagen and hence readily available, and uses a fluoride salt to install the fluoro group. Hence, the routes provide process-scale access to these useful nonnatural amino acids.
- Chorghade, Mukund S.,Mohapatra, Debendra K.,Sahoo, Gokarneswar,Gurjar, Mukund K.,Mandlecha, Manish V.,Bhoite, Nitin,Moghe, Santosh,Raines, Ronald T.
-
experimental part
p. 781 - 784
(2009/04/04)
-
- 4-Substituted-α,α-diaryl-prolinols improve the enantioselective catalytic epoxidation of α,β-enones
-
To seek novel metal-free organic catalysts for epoxidation with high stereoselectivity, a series of 4-substituted-α,α-diaryl-prolinols were synthesized in four steps from trans-4-hydroxyl-L-proline. These prolinol derivatives catalyzed the asymmetric epoxidation of α,β-enones to give the corresponding chiral epoxides in good yields and high enantioselectivities under mild reaction conditions. Studies of substituent effects on enantioselectivity revealed that steric bulk and electronic effect promoted higher enantioselectivity, and prolinol 8a was found to be the best catalyst until now.
- Li, Yawen,Liu, Xinyuan,Yang, Yingquan,Zhao, Gang
-
p. 288 - 291
(2007/10/03)
-
- Stereoselective synthesis of (1R,4R)-N-acyl-2-oxa-5-aza-bicyclo[2.2.1]heptan-3-ones via mesoionic compounds. An improved synthesis of cis-4-hydroxy-D-proline
-
We report an asymmetric synthesis of (1R,4R)-N-acyl-2-oxa-5-aza-bicyclo[2.2.1]heptan-3-ones, starting from the inexpensive and commercially available trans-4-hydroxy-L-proline and achieved by treating N-acyl-trans-4-hydroxy-L-prolines with acetic anhydride. The formation of intermediate mesoionic compounds may explain the formation of N-acyl-2-oxa-5-aza-bicyclo[2.2.1]heptan-3-ones with (R)-absolute configuration at C(4). Acidic cleavage of these lactones readily affords N-acyl-cis-4-hydroxy-D-prolines or cis-4-hydroxy-D-proline in good yields.
- Dalla Croce, Piero,La Rosa, Concetta
-
p. 197 - 201
(2007/10/03)
-