Facile Synthesis of C2-Symmetric Chiral Crown Ethers with Two Reactive Hydroxymethyl Groups - Nakatsuji, Yohji; Nakahara, Yoshio; Nagamiya, Katsumori; Itoh, Yuki; Uesugi, Kentaro; Ishida, Naohisa; Muraoka, Masahiro; Kida, Toshiyuki; Akashi, Mitsuru (Synthesis, 2007)