is u2014 h alkyl aryl or heteroaryl multiple degrees of substitution being allowed examples of u201c heteroaryl u201d groups used herein include furanyl thiophenyl pyrrolyl imidazolyl pyrazolyl triazolyl tetrazolyl thiazolyl oxazolyl isoxazolyl oxadiazolyl oxo pyridyl thiadiazolyl isothiazolyl pyridyl pyridazyl pyrazinyl pyrimidyl quinazolinyl quinolinyl isoquinolinyl benzofuranyl benzothiophenyl indolyl indazolyl and substituted versions thereof as used herein the term u201c alkoxy u201d refers to the group r a o u2014 where r a is alkyl as defined above and the terms u201c c 1 c 3 alkoxy u201d and u201c c 1 c 6 alkoxy u201d refer to an alkoxy group as defined herein wherein the alkyl moiety contains at least 1 and at most 3 or 6 carbon atoms exemplary u201c c 1 c 3 alkoxy u201d and u201c c 1 c 6 alkoxy u201d groups useful in the present invention include but are not limited to methoxy ethoxy n propoxy isopropoxy n butoxy and t butoxy as used herein the term u201c amino u201d refers to the group u2014 nh 2 as used herein the term u201c alkylamino u201d refers to the group u2014 nhr a wherein r a is alkyl as defined above as used herein the term u201c arylamino u201d refers to the group u2014 nhr a wherein r a is aryl as defined above as used herein the term u201c aralkylamino u201d refers to the group u2014 nhr a wherein r a is an aralkyl group as defined above as used herein the term u201c aralkoxy u201d refers to the group r b r a o u2014 where r a is alkylene and r b is aryl or heteroaryl all as defined above as used.