TY - JOUR AU - Dzięgielewski, Marek; Hejmanowska, Joanna; Albrecht, Łukasz TI - A Convenient Approach to a Novel Group of Quaternary Amino Acids Containing­ a Geminal Bisphosphonate Moiety SN - 0039-7881 SN - 1437-210X PY - 2014 JO - Synthesis JF - Synthesis LA - EN VL - 46 IS - 23 SP - 3233 EP - 3238 ET - 2014/08/26 DA - 2014/11/19 KW - azlactones KW - quaternary amino acids KW - geminal bisphosphonates KW - Michael addition KW - biologically relevant molecules AB - Quaternary amino acids containing a geminal bisphosphonate moiety have been synthesized for the first time. The developed two-step reaction sequence utilizes the Michael addition of α-substituted azlactones to a vinylidene bisphosphonate as the key step. The reaction proceeds under catalytic conditions with excellent regioselectivity. Subsequent, acid-mediated azlactone ring opening affords the target quaternary amino acids with good overall yields. Attempts to develop an enantioselective version of the synthetic strategy are described. PB - © Georg Thieme Verlag DO - 10.1055/s-0034-1378997 UR - http://www.thieme-connect.com/products/ejournals/abstract/10.1055/s-0034-1378997 ER -