Abstract: The present invention relates to imidazolyl thieno-benzothiepin derivatives of the Formula I: ##STR1## and acid addition salts thereof with pharmaceutically acceptable inorganic and organic acids, wherein R is a hydrogen or a chlorine atom. The invention also relates to processes for the preparation of these compounds. These compounds demonstrate substantial in vitro and in vivo antimycotic properties of the kind useful for the treatment of dermal and vaginal mycoses.The new compounds can be prepared by reacting 4,9-dihydrothieno(2,3-c)-2-benzothiepin-4-ol or its 6-chloro derivative with imidazole or a reactive derivative thereof, such as 1,1'-carbonyl-diimidazole or 1,1'-thionyldiimidazole; or by first converting the respective thieno-benzothiepin-4-ol into its alkane- or arenesulfonate ester, followed by reaction with imidazole.