A pharmaceutical composition, comprising a therapeutically effective amount of an active pharmaceutical ingredient (API) compound represented by the following structural formula

##STR00001## at least one acidifying agent; and a vehicle base comprising at least one pharmaceutically acceptable non-aqueous solvent. Values and preferred values of the variables in structural formula (I) are defined herein.

A pharmaceutical composition, comprising a therapeutically effective amount of an active pharmaceutical ingredient (API) compound represented by the following structural formula

##STR00001## at least one acidifying agent; and a vehicle base comprising at least one pharmaceutically acceptable non-aqueous solvent. Values and preferred values of the variables in structural formula (I) are defined herein.

A pharmaceutical composition, comprising a therapeutically effective amount of an active pharmaceutical ingredient (API) compound represented by the following structural formula

##STR00001## at least one acidifying agent; and a vehicle base comprising at least one pharmaceutically acceptable non-aqueous solvent. Values and preferred values of the variables in structural formula (I) are defined herein.

A pharmaceutical composition, comprising a therapeutically effective amount of an active pharmaceutical ingredient (API) compound represented by the following structural formula

##STR00001## at least one acidifying agent; and a vehicle base comprising at least one pharmaceutically acceptable non-aqueous solvent. Values and preferred values of the variables in structural formula (I) are defined herein.

Provided herein are brain penetrant histone deacetylase (HDAC) inhibitors useful for treating diseases or disorders associated with HDAC. An exemplary HDAC inhibitor provided herein exhibits a brain-to-plasma ratio of 20:1. Pharmaceutical compositions comprising HDAC inhibitors and methods for treating diseases associated with HDAC are also provided.

Provided herein are brain penetrant histone deacetylase (HDAC) inhibitors useful for treating diseases or disorders associated with HDAC. An exemplary HDAC inhibitor provided herein exhibits a brain-to-plasma ratio of 20:1. Pharmaceutical compositions comprising HDAC inhibitors and methods for treating diseases associated with HDAC are also provided.

Selective HDAC inhibitors, and pharmaceutical compositions that include the same, are described herein for the treatment of cancer, immunological diseases, inflammatory diseases, and neurological diseases.

The invention discussed in this application relates to hydroxamic acid-based compounds that are useful as imaging agents when bound to an appropriate metal centre, particularly for the imaging of tumours.

Disclosed herein are secondary amine compounds that inhibit tRNA synthetase. The compounds of the invention are useful in inhibiting tRNA synthetase in Gram-negative bacteria and are useful in killing Gram-negative bacteria. The secondary amine compounds of the invention are also useful in the treatment of tuberculosis.

This invention relates to methods for treating bone disease associated with osteoclast activation using HDAC6 selective inhibitors, e.g., small molecule inhibitors such as reverse amide compounds.