Succinic acid caffeine

T. Frii, A.V. Trask, W.D.S. Motherwell, W. Jones, Guest-directed assembly of caffeine and succinic acid into topologically different heteromolecular host networks upon grinding, Cryst. Growth Des. 8 (2008) 1605-1609. 

Figure 15 Comparison of the structures of the two caffeine-succinic acid hosts. For clarity, the dnmbbell-shaped building block (caf)2 (sa) is shown in orange and the additional pillars of sa (in framework 1) (a) and caf (in framework 2) (b) are shown in blue. Both host frameworks are based on a common building block a three-membered assembly of composition (caf)2-(sa) which are connected via C-H- -O hydrogen bonds into infinite linear chains. The guest molecules are disordered within the channels.

Figure 4.4 From left to right, molecular structures of caffeine, succinic acid and 4-aminobenzoic acid.

Figure 8.20 (a) Molecular diagrams of caffeine, succinic acid and pleuromutilin, (b)... 

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