Examples of amino groups include primary alkyl amino groups (i.e., --NHR; yielding a secondary amide group) and secondary alkyl amino groups (i.e., --NR2 ; yielding a tertiary amide group) where R may independently be an alkyl group of 1 to 10 carbon atoms, such as methyl (i.e., --CH3) and ethyl (i.e., --CH2 CH3).