5369-62-0Relevant articles and documents
PTERIN DERIVATIVE OR SALT THEREOF
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Paragraph 0064, (2017/07/23)
PROBLEM TO BE SOLVED: To provide a compound having nitrogen monooxide production promoting effect, blood vessel protecting effect, trace quantity albumin urine suppressing effect or the like superior to tetrahydrobiopterin (BH4), for compensating reduction of nitrogen monoxide productive function due to production reduction of BH4 in diabetes. SOLUTION: There is provided a pterin derivative represented by the formula (1) or a salt thereof. (1), where R1 is a specific linear/branched alkyl group, a cycloalkyl group, a cycloalkyl-alkyl group, an aryl group, an aralkyl group, a heterocyclic specific alkyl group or -CH(OH)CH3; R2 is absent, or H or a specific linear/branched alkyl group; R3 to R5 are each independently H or a single bond; R6 and R7 are each independently H or an aryl-alkyl group, a hydroxyalkyl group or an alkoxyalkyl group. SELECTED DRAWING: None COPYRIGHT: (C)2017,JPOandINPIT
Fluorinated organocatalysts for the enantioselective epoxidation of enals: Molecular preorganisation by the fluorine-iminium ion Gauche effect
Tanzer, Eva-Maria,Zimmer, Lucie E.,Schweizer, W. Bernd,Gilmour, Ryan
supporting information, p. 11334 - 11342,9 (2020/08/31)
The fluorine-iminium ion gauche effect is triggered upon union of a secondary β-fluoroamine and an α,β-unsaturated aldehyde, providing a useful strategy for controlling the molecular topology of intermediates that are central to organocatalytic processes. The β-fluoroamine (S)-2-(fluorodiphenylmethyl)pyrrolidine (1) is an effective catalyst for the enantioselective epoxidation of α,β-unsaturated aldehydes. A process of structural editing has revealed that the efficiency of this catalyst is due to the (fluorodiphenyl)methyl group when it is embedded in a β-fluoroiminium motif. Epoxidations of challenging cyclic α,β-disubstituted, β,β-disubstituted and α,β,β-trisubstituted enals catalysed by 1 proceed with excellent levels of enantiocontrol (up to 98 % ee). Fluorine finesse. The β-fluoroamine (S)-2-(fluorodiphenylmethyl)pyrrolidine (1) is an effective catalyst for the enantioselective epoxidation of α,β-unsaturated aldehydes (see scheme). Application of this catalyst to challenging cyclic α,β-disubstituted enals, β,β-disubstituted enals, and an α,β,β-trisubstituted enal proceeds in a highly enantioselective fashion (up to 98 % ee). Copyright
Diastereo- and enantioselective synthesis of functionalized β-lactams from oxiranecarbaldimines and lithium ester enolates
Michel, Kristin,Froehlich, Roland,Wuerthwein, Ernst-Ulrich
scheme or table, p. 5653 - 5665 (2010/03/03)
The addition of nucleophiles like lithium ester enolates 6 to oxiranecarbaldimines 1 leads to new oxiranyl-functionalised β-lactams 7 in excellent enantio- and diastereoselectivity. A simple one-pot procedure affords β-lactams (azetidin-2-ones) with three or four neighbouring stereogenic centres and unlike preference. Products resulting from oxirane ring-opening reactions were not observed. An enantiomerically enriched example (2S,3S)-1g gave the corresponding β-lactam (S,S,R)-7f in excellent enantiomeric excess. According to quantum chemical calculations the observed diastereoselectivity is the result of a diastereofacial differentiation of the two faces of the iminic double bond in the transition state.
