Please remove easychem from Debian. Its final upstream release was in
2005. It uses gtk2 which is being removed from Debian. It has had one
upload since 2013.

https://easychem.sourceforge.net/

As an alternative, I suggest ChemCanvas. It hasn't been packaged in
Debian yet but it is available on Flathub.

- https://github.com/ksharindam/chemcanvas
- https://flathub.org/en/apps/io.github.ksharindam.chemcanvas

Thank you,
Jeremy Bícha