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

Protecting-Group-Free Synthesis of Cassane-Type Furan Diterpenes via a Decarboxylative Dienone-Phenol Rearrangement. | LitMetric

Protecting-Group-Free Synthesis of Cassane-Type Furan Diterpenes via a Decarboxylative Dienone-Phenol Rearrangement.

Org Lett

Departamento de Química Orgánica, Facultad de Ciencias, Instituto de Biotecnología , Universidad de Granada , 18071 Granada , Spain.

Published: November 2018

An expeditious route to obtaining cassane-type furan diterpenes starting from (+)-sclareolide, an inexpensive commercially available natural lactone, has been achieved by using a solvent-free Diels-Alder cycloaddition and an unprecedented decarboxylative dienone-phenol rearrangement as key steps. Its applicability is showcased by the first synthesis of (5α)-vouacapane-8(14),9(11)-diene. The synthesis, which requires no protecting group, is efficient and atom- and step-economical (10 steps, 20% global).

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.orglett.8b02867DOI Listing

Publication Analysis

Top Keywords

cassane-type furan
8
furan diterpenes
8
decarboxylative dienone-phenol
8
dienone-phenol rearrangement
8
protecting-group-free synthesis
4
synthesis cassane-type
4
diterpenes decarboxylative
4
rearrangement expeditious
4
expeditious route
4
route obtaining
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!