Synthesis of 2-(1-aminocyclopropyl)pyrrolidine-3,4-diol derivatives applying titanium-mediated reaction conditions
摘要:
The titanium-mediated cyclopropanation reaction using Ti((OPr)-Pr-i)(3)Me/EtMgBr/BF3 center dot OEt2 has been applied to various 2-cyanopyrrolidines for the synthesis of functionalized 2-(1-aminocyclopropyl)pyrrolidine-3,4-diol derivatives (dideoxyiminoalditols). Under the same experimental conditions the trans-5-azidomethyl-2-cyanopyrrolidine derivative was not cyclopropanated but reduced into the corresponding 5-amino-2-cyano derivative. After polyol deprotection 2-(1-aminocyclopropyl)pyrrolidine-3,4-diols were obtained and their inhibitory activity towards 13 glycosidases has been evaluated. (2S,3S,4R,5S)-2-(1-Aminocyclopropyl)-5-methylpyrrolidine-3,4-diol (38), which has the same absolute configuration as L-fucose, is a moderate (IC50=44 mu M), but selective, inhibitor of alpha-L-fucosidase from human placenta. (C) 2011 Elsevier Ltd. All rights reserved.
One-pot synthesis of pyrrole derivatives from (E)-1,4-diaryl-2-butene-1,4-diones
作者:H Surya Prakash Rao、S Jothilingam
DOI:10.1016/s0040-4039(01)01334-x
日期:2001.9
2,5-Di- and 1,2,5-trisubstituted pyrrolederivatives can be prepared conveniently from (E)-1,4-diaryl-2-butene-1,4-diones in a one-pot operation through domino-pathways via palladium-assisted transfer hydrogenation followed by a Paal–Knorr reaction using ammonium formate and its analogs.
Synthesis of 5-substituted-3,4-dihydroxycyanopyrrolidines. An easy access to polyhydroxyprolines
作者:Marina Moura、Sébastien Delacroix、Denis Postel、Albert Nguyen Van Nhien
DOI:10.1016/j.tet.2009.01.108
日期:2009.4
A novel procedure for the synthesis of cyanopyrrolidines is presented. Starting from conveniently functionalized d-ribose, d-mannose, d-(l)-arabinose, the compounds were efficiently synthesised in four steps in overall good yields. Transformation into proline derivatives and preliminary evaluation of these derivatives in organocatalysis is also described.
Synthesis of 2-aminocyclopropyl pyrrolidines from glycoaminonitriles
作者:Delphine Declerck、Solen Josse、Albert Nguyen Van Nhien、Denis Postel
DOI:10.1016/j.tetlet.2009.02.135
日期:2009.5
We have developed an expedient method for the synthesis of 2-aminocyclopropyl pyrrolidinesfrom carbohydrate-derived α-aminonitriles involving up to five or six steps, the key step being the titanium-mediated aminocyclopropanation on the aminonitrile moiety, followed by cleavage of the protecting groups.
METHOD FOR ACYLATING HEXAKIS (ARYLMETHYL) HEXAAZAISOWURTZITANE
申请人:Asahi Kasei Kogyo Kabushiki Kaisha
公开号:EP1024141A1
公开(公告)日:2000-08-02
A method for acylating a hexakis(arylmethyl)hexaazaisowurtzitane (WB6) by reductive dearylmethylation in the presence of an acylating agent, which comprises contacting (a) a WB6 and (b) a heterogeneous reduction catalyst with each other in the presence of (c) an acylating agent and (d) a reducing agent in (e) a solvent for WB6 (a), thereby performing a reductive dearylmethylation/acylation reaction of WB6 (a), wherein there is no contact between WB6 (a) and heterogeneous reduction catalyst (b) in the absence of any of acylating agent (c) and reducing agent (d). The method of the present invention is commercially advantageous in that the decomposition of a hexaazaisowurtzitane skeleton, Which is likely to occur at the initial stage of the acylation reaction of a WB6 as a starting material, can be very effectively suppressed, so that desired tetraacylhexaazaisowurtzitane derivatives can be stably produced in high yield.