Abstract: Disclosed are compounds having structural formula I, and related pharmaceutical compositions. Also disclosed are therapeutic methods, e.g., of treating diseases such as diabetic kidney disease, diabetic nephropathy, obesity-related kidney disease, focal segmental glomerular sclerosis, IgA nephropathy, nephrotic syndrome, kidney fibrosis, Prader Willi syndrome, metabolic syndrome, gastrointestinal diseases, non-alcoholic liver disease, alcoholic liver disease, or non-alcoholic fatty liver disease, using the compounds of Formula (I).