Efficient Synthesis of N-[4-(4-Chlorophenyl)butyl]-S-(3-piperidinopropyl)isothiourea (OUP-186) and Its Analogues Using 2-Nitrophenylacetyl Isothiocyanate: Application to Novel Histamine H3R Antagonists - Yoneyama, Hiroki; Magata, Takuji; Uemura, Kenji; Usami, Yoshihide; Tanaka, Satoshi; Takaoka, Masanori; Harusawa, Shinya (Synthesis, 2015)