Petra Pharma Corp. has synthesized phosphatidylinositol 3-kinase α (PI3Kα) inhibitors, particularly H1047R and/or E545K mutant allosteric inhibitors. They are described as potentially useful for the treatment of cancer, PIK3CA-related overgrowth spectrum, congenital lipomatous overgrowth, vascular malformations, epidermal naevi and skeletal abnormalities.