Compare Two Enantiomers

Chemical components have defining features; even the smallest change will demonstrate different properties. With the Wolfram Language, you can access PubChem data and explore these features.

First, connect to the PubChem API.

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pubchem = ServiceConnect["PubChem"]

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Compare Vicks inhaler and methamphetamine, two substances that are commonly known and surprisingly related.

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compounds = pubchem["CompoundProperties", "Name" -> {"Vicks Inhaler", "Meth"}, "Property" -> {"MolecularFormula", "IUPACName"}]

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Retrieve and compare their 3D structure.

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{vicksid, methid} = Normal[compounds[All, "CompoundID"]]; Row[{pubchem["CompoundSDF", "CompoundID" -> vicksid]["Graphics3D", 1], pubchem["CompoundSDF", "CompoundID" -> methid]["Graphics3D", 1]}]

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Although they look the same, you can corroborate that they are indeed enantiomers by plotting their bonding structure and see that one is the mirror image of the other.

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{edgerule1, edgetype1, vertextype1} = Flatten[Values[ Normal[pubchem["CompoundSDF", "CompoundID" -> vicksid][{"EdgeRules", "EdgeTypes", "VertexTypes"}]]], 1]; vertexcoord1 = Thread[Rule[Range[1, Length[#]], #]] &@ Flatten[Normal[ pubchem["CompoundSDF", "CompoundID" -> vicksid][ "VertexCoordinates"]], 1]; {edgerule2, edgetype2, vertextype2} = Flatten[Values[ Normal[pubchem["CompoundSDF", "CompoundID" -> methid][{"EdgeRules", "EdgeTypes", "VertexTypes"}]]], 1]; vertexcoord2 = Thread[Rule[Range[1, Length[#]], #]] &@ Flatten[Normal[ pubchem["CompoundSDF", "CompoundID" -> methid][ "VertexCoordinates"]], 1]; normal[{x_, y_}] := 2.5*{-y, x}/Norm[{x, y}]; (Block[{name = #name, edgerule = #edgerules, vertextype = #vertextype, vertexcoord = #vertexcoord, edgetype = #edgetype}, name -> GraphPlot[edgerule, VertexRenderingFunction -> (Text[ Style[vertextype[[#2]], Bold], #1, Background -> White] &), VertexCoordinateRules -> vertexcoord, EdgeRenderingFunction -> (Switch[ Extract[edgetype, Position[ edgerule, (Rule @@ #) &@#2]], {"Single"}, {Purple, Line[#1]}, {"Double"}, norm = normal[First[#1] - Last[#1]]; {Orange, Thickness[0.005], Line[{First[#1] + norm, Last[#1] + norm}], Line[{First[#1] - norm, Last[#1] - norm}]}] &), ImageSize -> 200]] & /@ {<|"name" -> "Vicks Inhaler", "edgerules" -> edgerule1, "edgetype" -> edgetype1, "vertextype" -> vertextype1, "vertexcoord" -> vertexcoord1|>, <| "name" -> "Methamphetamine", "edgerules" -> edgerule2, "edgetype" -> edgetype2, "vertextype" -> vertextype2, "vertexcoord" -> vertexcoord2|>}) // Dataset

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