You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Chemical"].

Please return the output as a JSON object of the format: {"Chemical": ["Arsenic", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

Enantiospecific total synthesis of (-)-bengamide E. Total synthesis of the polyhydroxy caprolactam amide natural product, bengamide E, is accomplished starting from tartaric acid. Key reactions in the synthesis include desymmetrization of the bis(dimethylamide) unit of tartaric acid, Zn(BH(4))(2)-mediated anti-selective reduction, and a Horner-Wadsworth-Emmons olefination.
{"Chemical": ["Zn(BH(4))(2)", "polyhydroxy caprolactam amide", "tartaric acid", "bis(dimethylamide)", "bengamide E", "(-)-bengamide E"]}