The invention provides an acid addition salt of a compound of the formula (1) Also provided by the invention are processes for preparing the compound of formula (1) and alkyl analogues thereof, novel intermediates for use in the process and methods for preparing the intermediates. The invention also provides new medical uses of compounds of the formula (1) and its ethyl analogue.
The invention provides combinations comprising (or consisting essentially of) one or more ancillary compound(s) and a compound of the formula (I):
or salts, tautomers, solvates and N-oxides thereof; wherein R
1
is hydroxy or hydrogen; R
2
is hydroxy; methoxy or hydrogen; provided that at least one of R
1
and R
2
is hydroxy; R
3
is selected from hydrogen; halogen; cyano; optionally substituted C
1-5
hydrocarbyl and optionally substituted C
1-5
hydrocarbyloxy; R
4
is selected from hydrogen; a group —(O)
n
—R
7
where n is 0 or 1 and R
7
is an optionally substituted acyclic C
1-5
hydrocarbyl group or a monocyclic carbocyclic or heterocyclic group having 3 to 7 ring members; halogen; cyano; hydroxy; amino; and optionally substituted mono- or di-C
1-5
hydrocarbyl-amino; or R
3
and R
4
together form a monocyclic carbocyclic or heterocyclic ring of 5 to 7 ring members; and NR
5
R
6
forms an optionally substituted bicyclic heterocyclic group having 8 to 12 ring members of which up to 5 ring members are heteroatoms selected from oxygen, nitrogen and sulphur. The combinations have activity as Hsp90 and/or glycogen synthase kinase-3 and/or cyclin dependent kinase and/or aurora kinase inhibitors.