Download full text in PDF Opens in a new window. Article suggestions will be shown in a dialog on return to ScienceDirect. ... Please enable JavaScript to use all the features on this page. ... The identification of 2,3-dimethyl-5-(2,6,10-trimethylundecyl)thiophene as a major constituent of certain petroleums and sediment extracts was confirmed by synthesis of the standard. ... The identification of 2,3-dimethyl-5-(2,6,10-trimethylundecyl)thiophene (I) as a major ...