七彩星D(1,C26H30O5)和monadelphinA(2,C30H36O11)的晶体结构,维拉菌素和gedunin类柠檬苦素的生物活性分子,分别,首次报道了影响其晶体填充的合成子,并根据它们在剑桥结构数据库中共享相同部分的分子中的出现情况进行了分析。冬凌草素D,1,以空间群P21结晶,其分子结构由三个六元环A组成,C和D有,分别,信封,扭转船和半椅子构造,和三个具有半椅子(B和E)和平面构象(F)的五元环。在1的晶体堆积中发现的许多合成子与来自显示相同部分的分子的预期一致。然而,仲醇-酮O-H。..O=Csynthon,发生率较低(2.9%),对分层包装有很大贡献,而呋喃酮Csp2-H..O=C和仲醇-环氧化物O-H。..通常在这些化合物中发现的OC2合成子(出现20.6%和17.6%,分别)失踪。1的包装接近ceramicineB(3),但与TS3(4)完全不同,表明3中不存在环氧基团会有利于呋喃仲醇Csp2-H。..OH合成子和4中缺失的羟基,一个强氢键供体,将有利于水分子参与晶体堆积。monadelphinA的分子结构,2,由四个六元稠环组成(A,B,C和D)和一个五元环(E);它们具有扭转船(A和C),主席(B),螺旋舟(D)和平面(E)构象。该分子在空间群P212121中结晶,通常在具有相同部分的化合物中发现许多合成子。然而,仲醇-乙酸酯O-H。..OOC和仲醇-酮O-H...O=C合成子(在这些化合物中各出现16.7%)缺失。呋喃乙酸酯Csp2-H。..在这些化合物中未观察到的OOC合成子大大有助于2的分层堆积。层状包装与7-氧代杜宁(5)和6-脱氢-7-脱乙酰氧基-7-氧代杜宁(6)非常接近,两者都在空间群P21中结晶。
The crystal structures of rubescin D (1, C26H30O5) and monadelphin A (2, C30H36O11), bioactive molecules of the vilasinin and gedunin classes of limonoids, respectively, are reported for the first time and the synthons affecting their crystal packings are analyzed on the basis of their occurrences in molecules in the Cambridge Structural Database that share the same moieties. Rubescin D, 1, crystallizes in the space group P21 and its molecular structure consists of three six-membered rings A, C and D having, respectively, envelope, twist-boat and half-chair conformations, and three five-membered rings with half-chair (B and E) and planar conformations (F). Many synthons found in the crystal packing of 1 are in agreement with expectations derived from molecules displaying the same moieties. However, the secondary alcohol-ketone O-H...O=C synthon, which has a low occurrence (2.9%), contributes much to the layered packing, while the furan-ketone Csp2-H...O=C and secondary alcohol-epoxide O-H...OC2 synthons usually found in these compounds (occurrences of 20.6 and 17.6%, respectively) are missing. The packing of 1 is close to that of ceramicine B (3), but is completely different from that of TS3 (4), suggesting that the absence of the epoxide group in 3 would have favoured the furan-secondary alcohol Csp2-H...OH synthon and that the missing hydroxy group in 4, a strong hydrogen-bond donor, would have favoured the involvement of water molecules in the crystal packing. The molecular structure of monadelphin A, 2, consists of four six-membered fused rings (A, B, C and D) and one five-membered ring (E); they have twist-boat (A and C), chair (B), screw-boat (D) and planar (E) conformations. The molecule crystallizes in the space group P212121 with the contribution of many synthons usually found in compounds having the same moieties. However, the secondary alcohol-acetate O-H...OOC and secondary alcohol-ketone O-H...O=C synthons (occurrences of 16.7% each in these compounds) are missing. The furan-acetate Csp2-H...OOC synthon not observed in these compounds greatly contributes to the layered packing of 2. The layered packing is very close to those of 7-oxogedunin (5) and 6-dehydro-7-deacetoxy-7-oxogedunin (6), which both crystallize in the space group P21.