A PHP Error was encountered

Severity: Warning

Message: file_get_contents(https://...@pubfacts.com&api_key=b8daa3ad693db53b1410957c26c9a51b4908&a=1): Failed to open stream: HTTP request failed! HTTP/1.1 429 Too Many Requests

Filename: helpers/my_audit_helper.php

Line Number: 176

Backtrace:

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 176
Function: file_get_contents

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 250
Function: simplexml_load_file_from_url

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3122
Function: getPubMedXML

File: /var/www/html/application/controllers/Detail.php
Line: 575
Function: pubMedSearch_Global

File: /var/www/html/application/controllers/Detail.php
Line: 489
Function: pubMedGetRelatedKeyword

File: /var/www/html/index.php
Line: 316
Function: require_once

Synthesis of polysubstituted β-amino cyclohexane carboxylic acids via Diels-Alder reaction using Ni(II)-complex stabilized β-alanine derived dienes. | LitMetric

Synthesis of polysubstituted β-amino cyclohexane carboxylic acids via Diels-Alder reaction using Ni(II)-complex stabilized β-alanine derived dienes.

Amino Acids

State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, People's Republic of China.

Published: February 2013

This paper describes the design and synthesis of a new class of β-alanine derived dienes stabilized by Ni(II)-complex. Preliminary study of their Diels-Alder cycloaddition reactions with several types of dienophiles demonstrates their significant synthetic potential for the preparation of various polyfunctional β-aminocyclohexane carboxylic acids.

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00726-012-1404-xDOI Listing

Publication Analysis

Top Keywords

carboxylic acids
8
β-alanine derived
8
derived dienes
8
synthesis polysubstituted
4
polysubstituted β-amino
4
β-amino cyclohexane
4
cyclohexane carboxylic
4
acids diels-alder
4
diels-alder reaction
4
reaction niii-complex
4

Similar Publications

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!