diff --git a/pyproject.toml b/pyproject.toml
index 19196e5..7a2e035 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -58,6 +58,7 @@ interactive = [
 ]
 chemdb = [
     "cirpy",
+    "pubchempy",
     "chemspipy",
 ]