title: Synthesis of 1,19-Aza-1,19-desoxy-avermectin B(1a): The First Avermectin Macrolactam.
abstract: The first synthesis of 1,19-aza-1,19-desoxy-avermectin B(1a) (2) is described. This new macrolactam, prepared efficiently from avermectin B(1a) (1a) in seven steps, was designed to form an intramolecular hydrogen bond between the amide carbonyl and the adjacent C7 tertiary hydroxyl via a six-center hydrogen bonding network. The presence of this intramolecular hydrogen bond is anticipated to confer additional conformational rigidity to the 16-membered macrocycle.
authors.affiliation: Merck Research Laboratories, Department of Basic Medicinal Chemistry, P.O. Box 2000, Rahway, New Jersey 07065-0900.
authors.forename: Peter T.
authors.initials: PT
authors.lastname: Meinke
authors.forename: Byron
authors.initials: B
authors.lastname: Arison
authors.forename: J. Chris
authors.initials: JC
authors.lastname: Culberson
authors.forename: Michael H.
authors.initials: MH
authors.lastname: Fisher
authors.forename: Helmut
authors.initials: H
authors.lastname: Mrozik