The compounds of formula I are useful both in the free base form and in the form of {HEAD ~ acid addition salts}, and, both forms are within {TAIL ~ the purview} of the invention 
The compounds of formula I are useful both in the free base form and in the form of { HEAD ~ acid addition salts } , and , both forms are within { TAIL ~ the purview } of the invention
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH