title: Redetermination and absolute configuration of atalaphylline.
abstract: THE TITLE ACRIDONE ALKALOID [SYSTEMATIC NAME: 1,3,5-trihydr-oxy-2,4-bis-(3-methyl-but-2-en-yl)acridin-9(10H)-one], C(23)H(25)NO(4), has previously been reported as crystallizing in the chiral ortho-rhom-bic space group P2(1)2(1)2(1) [Chantrapromma et al. (2010 ▶). Acta Cryst. E66, o81-o82] but the absolute configuration could not be determined from data collected with Mo radiation. The absolute configuration has now been determined by refinement of the Flack parameter with data collected using Cu radiation. All features of the mol-ecule and its crystal packing are similar to those previously described.
authors.forename: Hoong-Kun
authors.initials: HK
authors.lastname: Fun
authors.forename: Chin Sing
authors.initials: CS
authors.lastname: Yeap
authors.forename: Suchada
authors.initials: S
authors.lastname: Chantrapromma