Gomes Ligia R, Low John Nicolson, Oliveira Catarina, Cagide Fernando, Borges Fernanda
REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre, 687, P-4169-007, Porto, Portugal; FP-ENAS-Faculdade de Ciências de Saúde, Escola Superior de Saúde da UFP, Universidade Fernando Pessoa, Rua Carlos da Maia, 296, P-4200-150 Porto, Portugal.
Department of Chemistry, University of Aberdeen, Meston Walk, Old Aberdeen AB24 3UE, Scotland.
Acta Crystallogr E Crystallogr Commun. 2016 Apr 15;72(Pt 5):675-82. doi: 10.1107/S2056989016005958. eCollection 2016 May 1.
The crystal structures of three benzamide derivatives, viz. N-(6-hy-droxy-hex-yl)-3,4,5-tri-meth-oxy-benzamide, C16H25NO5, (1), N-(6-anilinohex-yl)-3,4,5-tri-meth-oxy-benzamide, C22H30N2O4, (2), and N-(6,6-di-eth-oxy-hex-yl)-3,4,5-tri-meth-oxy-benzamide, C20H33NO6, (3), are described. These compounds differ only in the substituent at the end of the hexyl chain and the nature of these substituents determines the differences in hydrogen bonding between the mol-ecules. In each mol-ecule, the m-meth-oxy substituents are virtually coplanar with the benzyl ring, while the p-meth-oxy substituent is almost perpendicular. The carbonyl O atom of the amide rotamer is trans related with the amidic H atom. In each structure, the benzamide N-H donor group and O acceptor atoms link the mol-ecules into C(4) chains. In 1, a terminal -OH group links the mol-ecules into a C(3) chain and the combined effect of the C(4) and C(3) chains is a ribbon made up of screw related R 2 (2)(17) rings in which the ⋯O-H⋯ chain lies in the centre of the ribbon and the tri-meth-oxy-benzyl groups forms the edges. In 2, the combination of the benzamide C(4) chain and the hydrogen bond formed by the terminal N-H group to an O atom of the 4-meth-oxy group link the mol-ecules into a chain of R 2 (2)(17) rings. In 3, the mol-ecules are linked only by C(4) chains.
描述了三种苯甲酰胺衍生物的晶体结构，即N-(6-羟基己基)-3,4,5-三甲氧基苯甲酰胺（C₁₆H₂₅NO₅，(1)）、N-(6-苯胺基己基)-3,4,5-三甲氧基苯甲酰胺（C₂₂H₃₀N₂O₄，(2)）和N-(6,6-二乙氧基己基)-3,4,5-三甲氧基苯甲酰胺（C₂₀H₃₃NO₆，(3)）。这些化合物仅在己基链末端的取代基不同，而这些取代基的性质决定了分子间氢键的差异。在每个分子中，间甲氧基取代基实际上与苄环共面，而对甲氧基取代基几乎垂直。酰胺旋转异构体的羰基O原子与酰胺H原子呈反式关系。在每个结构中，苯甲酰胺N-H供体基团和O受体原子将分子连接成C(4)链。在(1)中，一个末端-OH基团将分子连接成C(3)链，C(4)链和C(3)链的综合作用形成了一条由螺旋转关的R₂(2)(17)环组成的带，其中⋯O-H⋯链位于带的中心，三甲氧基苄基基团形成边缘。在(2)中，苯甲酰胺C(4)链与末端N-H基团与4-甲氧基的一个O原子形成的氢键相结合，将分子连接成R₂(2)(17)环的链。在(3)中，分子仅通过C(4)链连接。
