1. Chemistry and Drug Metabolism; Intramural Research Program; National Institute on Drug Abuse; National Institutes of Health; Baltimore MD USA
2. Designer Drug Research Unit; Intramural Research Program; National Institute on Drug Abuse; National Institutes of Health; Baltimore MD USA
3. Drug Design and Synthesis Section; Intramural Research Program; National Institute on Drug Abuse and National Institute on Alcohol Abuse and Alcoholism; National Institutes of Health; Baltimore MD USA
4. On leave from the Medicinal Chemistry Group; Qs’ Research Institute; Otsuka Pharmaceutical Co., Ltd.; Tokushima Japan