#$%^&*AU2016234985B220180201.pdf#####H:\rec\Intrwovn\NRPortbl\DCC\REC\l1488137_ .docx-29/09/2016 Abstract The invention provides compounds of formula I: or a salt thereof as described herein. The invention also provides pharmaceutical compositions comprising a compound of formula 5 I, processes for preparing compounds of formula I, intermediates useful for preparing compounds of formula I and therapeutic methods for treating the proliferation of the HIV virus, treating AIDS or delaying the onset of AIDS or ARC symptoms in a mammal using compounds of formula I.