[{"from": "human", "value": "Create a molecule that satisfies the conditions outlined in the description. The molecule is the ethyl ester of prop-2-ynoic acid. It is a ynoate ester, a terminal acetylenic compound and an ethyl ester."}, {"from": "gpt", "value": "[C][C][O][C][=Branch1][C][=O][C][#C]"}]