Concise and Diversity-Oriented Route toward Polysubstituted 2-Aminoimidazole Alkaloids and Their Analogues
作者:Denis S. Ermolat'ev、Jitender B. Bariwal、Hans P. L. Steenackers、Sigrid C. J. De Keersmaecker、Erik V. Van der Eycken
DOI:10.1002/anie.201004256
日期:2010.12.3
Alkaloids of the naamine family were synthesized from diverse propargylamines in just two steps (see scheme: R1=Me, R2=substituted benzyl, R3=Ar). Thus, the addition to a propargylamine of a carbodiimide generated in situ, silver(I)‐catalyzed intramolecular hydroamidation, and subsquent deprotection provide access to the heterocyclic core of numerous natural products and biologically active compounds
A Catalytic Asymmetric Pictet–Spengler Platform as a Biomimetic Diversification Strategy toward Naturally Occurring Alkaloids
作者:Manuel J. Scharf、Benjamin List
DOI:10.1021/jacs.2c06664
日期:2022.8.31
N-carbamoyl-β-arylethylamines with diverse aldehydes toward enantioenriched THIQs. The obtained products proved to be competent intermediates in the synthesis of THIQ, aporphine, tetrahydroberberine, morphinan, and androcymbine natural products. Novel catalyst design with regard to the stabilization of cationic intermediates was crucial to accomplish high reactivity while simultaneously achieving unprecedented
Strategies for the construction of morphinan alkaloid AB-rings: regioselective Friedel-Crafts-type cyclisations of γ-aryl-β-benzoylamido acids with asymmetrically substituted γ-aryl rings
作者:Stephen G. Davies、Euan C. Goddard、Paul M. Roberts、Angela J. Russell、Andrew D. Smith、James E. Thomson、Jonathan M. Withey
DOI:10.1016/j.tetasy.2016.02.010
日期:2016.4
The regioselectivity of the Friedel-Crafts-type cyclisation of a range of gamma-aryl-B-benzoylamido acids, bearing oxy substituents at the C(3)- and C(4)-positions of the gamma-aryl ring, has been investigated. In all of the cases examined (with 3,4-dimethoxy, 3,4-methylenedioxy and 3-hydroxy-4-methoxy substituents) the Lewis acid promoted cyclisation proceeds with exclusive regioselectivity for attack at the C(6)-position rather than at the C(2)-position, and furnishes the corresponding N- and O-protected 3-amino-6,7-dihydroxy-1-tetralone derivatives. This inherent regioselectivity can be overturned by the regioselective introduction of chlorine as a blocking group for the C(6)-position; subsequent Lewis acid promoted cyclisation then proceeds with exclusive regioselectivity for attack at the C(2)-position to deliver the corresponding N- and O-protected 3-amino-5-chloro-7,8-dihydroxy-1-tetralone derivative. These complementary cyclisation protocols represent useful methods for the preparation of these benzo-fused carbocyclic ring systems, which are the functionalised AB-rings of a range of morphinan alkaloids. (C) 2016 Published by Elsevier Ltd.
[EN] PROCESSES FOR THE PREPARATION OF THE ENANTIOMERS OF 3,4-METHYLENEDIOXYMETHAMPHETAMINE (MDMA) AND N-METHYL-1,3-BENZODIOXOLYLBUTANAMINE (MBDB)<br/>[FR] PROCÉDÉS DE PRÉPARATION DES ÉNANTIOMÈRES DE LA 3,4-MÉTHYLÈNEDIOXYMÉTHAMPHÉTAMINE (MDMA) ET DE LA N-MÉTHYL-1,3-BENZODIOXOLYLBUTANAMINE (MBDB)
申请人:[en]PHARMALA BIOTECH INC.
公开号:WO2022232949A1
公开(公告)日:2022-11-10
The present application includes a process for preparing the (R)- or (S)- enantiomers of 3,4-methylenedioxymethamphetamine ((R)-MDMA or (S)-MDMA) and (R)- or (S)-N-methyl-1,3-benzodioxolylbutanamine ((R)-MBDB or (S)-MBDB) using (R)- tert-butanesulfinamide or (S)-tert-butanesulfinamideas a chiral auxiliary. (I) The present application also includes novel intermediate compounds useful in the preparation of (R/S)-MDMA and (R/S)-MBDB.
The total synthesis of berberine and selected analogues, and their evaluation as amyloid beta aggregation inhibitors
The total synthesis of berberine and selected analogues. And their evaluation as amyloid β (Aβ) aggregation inhibitors is described. The key step in the synthesis, the assembly of the berberine framework, was accomplished using an intermolecular Heck reaction. Berberine analog 17 incorporating a tertiary amine moiety showed good anti Aβ aggregation activity, water solubility, and almost no toxicity