This invention provides some new synthetically obtained compounds of formula (I and II), which are useful as chemical intermediates. Representative formula (I or II) compounds have also been shown to possess useful ranges of antitumor activity in standard laboratory animal tests. In addition, the compounds of formula (I or II) can be linked to monoclonal antibodies, either directly or via known linking group, as a means of selectively delivering the CC-1065 analogs (Compounds of Formula I and II) to those target cells expressing the target antigen and thus selectively eliminating those diseased cells from the animal or human. Further, the compounds of formula (I and II) can be linked to soluble human CD4 or a soluble human CD4 protein fragment capable of binding to the gp120 envelope protein of the human immuno-virus and thus eliminate virally infected cells.