ARS | Publication request: DIMERIC BETA ETHER THIOACIDOLYSIS PRODUCTS RESULTING FROM INCOMPLETE ETHER CLEAVAGE

Submitted to: Holzforschung
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 11, 1996
Publication Date: N/A

Interpretive Summary: Lignin is a complex component of forage plants. It can be analyzed by a number of methods. A technique called thioacidolysis, developed in France, is becoming popular because of the valuable information it provides about the type and structure of lignin. The method utilizes chemical reactions to break ether bonds in lignin. However, we have been finding products from plant materials following thioacidolysis that appeared to be ether- linked; i.e., not all of the ether bonds were being broken. We firmly identified these products by independently preparing each of the four of them and comparing their chemical characteristics. Researchers who use thioacidolysis are urged to look for these products of incomplete ether cleavage and account for them in their analytical data.

Technical Abstract: The four beta-ether dimers which result from incomplete b-ether cleavage of syringyl-guaiacyl lignins following thioacidolysis/desulfurization [3-(4- hydroxy-3-methoxyphenyl)-2-(2-methoxy-4-propylphenoxy)propan-1-ol, 2-(2,6- dimethoxy-4-propylphenoxy)-3-(4-hydroxy-3-methoxyphenyl)propan-1-ol, 3-(3,5 dimethoxy-4-hydroxyphenyl)-2-(2-methoxy-4-propylphenoxy)propan-1-ol, and 3- -(3,5-dimethoxy-4-hydroxyphenyl)-2-(2,5-dimethoxy-4-propylphenoxy)propan-1- ol] were identified from plant materials. Each dimer was synthesized for authentication by modifying dimeric lignin model beta-ether strategies.