the present invention, inflammatory diseases, cancer, and diseases and conditions, including AIDS as agents in the treatment provides an acceptable salt thereof and a pharmaceutically useful compound formula I. Formula I In Formula I, R 1 , R 2 , R 6 , Y 1 , Y 2 , Y 3 , A 1 , A 2 , A 3 , and A 4 It has any of the values defined in the specification. In another aspect, the present invention provides a pharmaceutical composition comprising at least one compound of formula I,