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:

Sesquiterpenes from the rhizomes of Curcuma heyneana. Four new germacranes [heyneanones A-D (1-4)], three new guaianes [4,10-epizedoarondiol (5), 15-hydroxyprocurcumenol (6), 12-hydroxycurcumenol (7)], and two new spirolactones [curcumanolides C (8) and D (9)] were isolated from the rhizomes of Curcuma heyneana together with 13 known sesquiterpenes and two known labdane-type diterpenes. Among the isolated compounds, heyneanone A (1), heyneanone C (3), 4,10-epizedoarondiol (5), procurcumenol (16), aerugidiol (17), zerumin A (23), and (E)-15,16-bisnorlabda-8(17),11-dien-13-one (24) inhibited protein tyrosine phosphatase 1B (PTP1B) with IC(50) values of 42.5, 35.2, 35.1, 45.6, 35.7, 10.4, and 14.7 μM, respectively.
{"Chemical": ["labdane", "zerumin A", "sesquiterpenes", "15-hydroxyprocurcumenol", "(E)-15,16-bisnorlabda-8(17),11-dien-13-one", "heyneanone C", "diterpenes", "12-hydroxycurcumenol", "Sesquiterpenes", "curcumanolides", "heyneanone A", "aerugidiol", "guaianes", "spirolactones", "germacranes", "4,10-epizedoarondiol", "tyrosine", "heyneanones A-D", "procurcumenol"]}