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2 posts tagged notations.

Apr 28, 2026

Reactions and retrosynthesis from 1985 to today

How reactions are written down and searched backwards, from RXN files, reaction SMILES and SMIRKS to the USPTO and ORD datasets and open retrosynthesis tools.

reactionsretrosynthesisnotationssmiles
Henry reactionbase
O + N+OO− O−N+O
Benzaldehyde1.0 equiv10.6 gNitromethane1.0 equiv6.1 gn-Butylamine0.1 equiv0.73 g
Apr 25, 2026

Chemistry line notations from 1949 to today

How chemists write a molecule as one line of text, from WLN and SMILES to InChI and the notations made for machine learning, with caffeine as the running example.

notationssmilesinchicheminformatics
CaffeineSMILES
NONNNO
CN1C=NC2=C1C(=O)N(C(=O)N2C)C InChIKeyRYYVLZVUVIJVGH-UHFFFAOYSA-N CAS58-08-2
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