- Synthesis and structure-activity relationships of isoxazole carboxamides as growth hormone secretagogue receptor antagonists. Xin, Z., Zhao, H., Serby, M.D., Liu, B., Schaefer, V.G., Falls, D.H., Kaszubska, W., Colins, C.A., Sham, H.L., Liu, G. Bioorg. Med. Chem. Lett. (2005)