This invention involves compounds having the following structure: wherein: a) R1 is
hydrogen; or
alkyl; bond (a) is a single or a
double bond; b) R2 and R3 are each independently selected from
hydrogen; unsubstituted C1-C3 alkanyl, alkenyl or alkynyl; cycloalkanyl, cycloalkenyl; unsubstituted C1-C3 alkylthio or alkoxy; hydroxy;
thio; nitro; cyano; amino; C1-C3 alkylamino or C1-C3 dialkylamino and halo; c) R4, R5 and R6 are each independently selected from
hydrogen; unsubstituted C1-C3 alkanyl, alkenyl or alkynyl; cycloalkanyl, cycloalkenyl; unsubstituted C1-C3 alkylthio or alkoxy; hydroxy;
thio; nitro; cyano; amino; C1-C3 alkylamino or C1-C3 dialkylamino; halo; and 2-imidazolinylamino; and wherein one and only one of R4, R5 and R6 is 2-imidazolinylamino; d) R7 is selected from hydrogen; unsubstituted C1-C3 alkanyl, alkenyl or alkynyl; cycloalkanyl, cycloalkenyl; unsubstituted C1-C3 alkylthio or alkoxy; hydroxy;
thio; nitro; cyano; amino; C1-C3 alkylamino or C1-C3 dialkylamino and halo; e) the compound is not 4-(2-imidazolinylamino)indole; enantiomers, optical isomers, stereoisomers, diastereomers, tautomers, addition salts, biohydrolyzable amides and esters thereof, and pharmaceutical compositions comprising such novel compounds. The invention also relates to the use of such compounds for treating disorders modulated by alpha-2 adrenoceptors.