A flexible asymmetric approach to methyl 5-alkyltetramates and its application in the synthesis of cytotoxic marine natural product belamide a.

Summary of "A flexible asymmetric approach to methyl 5-alkyltetramates and its application in the synthesis of cytotoxic marine natural product belamide a."

By using a methyl tetramate derivative (R)- or (S)-9 as a novel chiral building block, a direct, flexible, and highly enantioselective approach to methyl (R)- or (S)-5-alkyltetramates (2) is disclosed. Among the synthesized methyl 5-alkyltetramates 2, methyl 5-methyltetramate (2 a) is found in cytotoxic mirabimide E (4) and dysideapyrrolidone (5), and methyl 5-benzyltetramate (2 g) is a substructure in the potent antineoplastic dolastatin 15 (3). On the basis of this method, the first asymmetric synthesis of the antimitotic tetrapeptide belamide A (7) has been achieved in seven steps from (S)-9, with an overall yield of 23.8 %. Not only have the structure and absolute configuration of (+)-belamide A (7) been confirmed, but also the solvent used for recording the (13) C NMR spectrum, the (13) C NMR spectrum data correlation, and optical rotation data of natural belamide A (7) have been revised.


Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005 (P.R. China), Fax: (+86) 592-2186400.

Journal Details

This article was published in the following journal.

Name: Chemistry (Weinheim an der Bergstrasse, Germany)
ISSN: 1521-3765
Pages: 958-68


DeepDyve research library

PubMed Articles [22347 Associated PubMed Articles listed on BioPortfolio]

Asymmetric transformations of achiral 2,5-cyclohexadienones.

Cyclohexadienones are versatile platforms for performing asymmetric synthesis as evidenced by the numerous natural product syntheses that exploit their diverse reactivity profile. However, there are f...

Asymmetric 1,4-bis(ethynyl)bicyclo2.2.2octane rotators via monocarbinol functionalization. Ready access to polyrotors.

Asymmetric rotators with a 1,4-bis(ethynyl)bicyclo[2.2.2]octane (BCO) core are needed for engineering crystalline arrays of functional molecular rotors. Their synthesis uses carbinol, 2-methyl-3-butyn...

Asymmetric Synthesis of Heterocyclic Analogues of a CGRP Receptor Antagonist for Treating Migraine.

An asymmetric synthesis of novel heterocyclic analogue of the CGRP receptor antagonist rimegepant (BMS-927711, 3) is reported. The cycloheptane ring was constructed by an intramolecular Heck reaction....

Asymmetric Synthesis of (+)-anti- and (-)-syn-Mefloquine Hydrochloride.

The asymmetric (er > 99:1) total synthesis of (+)-anti- and (-)-syn-mefloquine hydrochloride from a common intermediate is described. The Sharpless asymmetric dihydroxylation is the key asymmetric tra...

The first asymmetric synthesis of marliolide from readily accessible carbohydrate as chiral template.

A simple and efficient strategy for the first asymmetric total synthesis of marliolide was accomplished by using stereoselective alkylation of the dianion of the β-hydroxy lactone enolate with myrist...

Clinical Trials [2976 Associated Clinical Trials listed on BioPortfolio]

Rigid Versus Flexible Cystoscopy in Women

The study will help define the best tolerated approach to cystoscopy in women by randomly comparing flexible to rigid cystoscopy. Previous randomized studies evaluated rigid cystoscopy und...

Flexible vs Rigid Cytoscopy in Women

This study will help define the best tolerated approach to cystoscopy by randomly comparing the flexible to the rigid cystoscope.

Evaluation of Topic Anaesthesia for Laryngoscopy With Fibroscopy During Paediatric Ear Nose Throat (ENT)Consultation

The purpose of this work is to estimate the efficiency in terms of pain of the application of a local anesthetic (xylocaïne viscous 2%®) during the realization of an examination in naso-...

A Study Evaluating the Effects of Lipid Lowering Treatment on Steroid Synthesis

Cholesterol is the precursor of glucocorticoids, mineralocorticoids and sex steroids. Both adrenal and non-adrenal (ovarian + testicular) all steroid hormones are primarily synthesized usi...

Evaluation of the Single Use Flexible Optical Scope Versus Multiple Use Flexible Optical Scopes for Intubation

The study is in two parts Part one of the study describes the use of the new single-use flexible video-scope for intubation of patients with predicted normal airways. Part two comp...

Medical and Biotech [MESH] Definitions

A cytotoxic polypeptide quinoxaline antibiotic isolated from Streptomyces echinatus that binds to DNA and inhibits RNA synthesis.

(1 beta,2 alpha,11 beta,12 alpha,15 beta(S))-11,20-Epoxy-1,2,11,12-tetrahydroxy-15-(2-hydroxy-2-methyl-1-oxobutoxy)picras-3-en-16-one. A quassinoid (Simaroubolide) from Simaruba glauca, a tropical shrub. It has been used as an antiamebic agent and is found to be cytotoxic. It may be of use in cancer chemotherapy.

Any situation where an animal or human is trained to respond differentially to two stimuli (e.g., approach and avoidance) under reward and punishment conditions and subsequently trained under reversed reward values (i.e., the approach which was previously rewarded is punished and vice versa).

A cytokine which resembles IL-1 structurally and IL-12 functionally. It enhances the cytotoxic activity of NK CELLS and CYTOTOXIC T-LYMPHOCYTES, and appears to play a role both as neuroimmunomodulator and in the induction of mucosal immunity.

Brief therapeutic approach which is ameliorative rather than curative of acute psychiatric emergencies. Used in contexts such as emergency rooms of psychiatric or general hospitals, or in the home or place of crisis occurrence, this treatment approach focuses on interpersonal and intrapsychic factors and environmental modification. (APA Thesaurus of Psychological Index Terms, 7th ed)

Quick Search

DeepDyve research library

Searches Linking to this Article