The /m and /s layersStep 15 of 17 of the InChI walkthrough. A structure and its mirror image would otherwise give two unrelated /t layers. Instead InChI writes whichever of the two is smaller and adds a mirror flag: /m0 if the compound is the one written, /m1 if it is the mirror image. The /s layer then states the stereo type — 1 absolute, 2 relative, 3 racemic. Both tartaric acid enantiomers carry /t1-,2-; only /m tells them apart.It opens on O[C@H]([C@@H](O)C(=O)O)C(=O)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.

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Tests — the IUPAC regression corpora

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