ppchtex – Typeset chemical formula diagrams
ppchTeX is a separate module of the ConTeXt macro package for TeX. It seems to be in its final state (having not changed for more than 10 years).
Maybe you are interested in the following packages as well.
- context-typearea: Something like Koma-Script typearea
- context-visualcounter: Visual display of ConTeXt counters
- context-annotation: Annotate text blocks
- context-simplefonts: Simplified font usage for ConTeXt