The /c connections layerStep 7 of 17 of the InChI walkthrough. The connection table is a depth-first walk over the numbered skeleton. Start at the atom with the fewest neighbours, walk as deep as you can, and write down the numbers you meet. Dashes join a chain, parentheses hold the branches at an atom, and a repeated number is a ring closure rather than a new atom.It opens on CCOC(C)=O, drawn live, so the layer under discussion changes as you change the structure.Convert a structure to its InChI and InChIKey and back, convert a whole CSV, XLSX or SDF file, learn how the identifier is derived, and practise writing its layers. The InChI engine is WebAssembly running in your browser, so the tool needs JavaScript — and nothing you open ever leaves your machine.

Convert — a structure in, an InChI out

Batch — a whole CSV, XLSX or SDF file

Tutorial — how an InChI is derived

Exercises — write the layers yourself

Cheatsheet — every layer in a table

Tests — the IUPAC regression corpora

Download — take the engine away

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