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:

A new abietane diterpenoid from Salvia xanthocheila Boiss. From the chloroform extract of aerial part of Salvia xanthocheila Boiss. one new abietane diterpenoid, xantoquinone (5α,6α-dimethoxy-7,11,14-trioxoabieta-8,12-diene) and one known oleanene triterpenoid namely 1β,3β-dihydroxy-12-oleanene were isolated. The structure of the new terpenoid was elucidated by comprehensive spectroscopic analysis including electron ionisation-mass spectra, (1)H NMR, (13)C NMR, distortionless enchancement by polarisation transfer, H,H correlation spectroscopy, heteronuclear multiple-quantum coherence and heteronuclear multiple-bond correlation.
{"Chemical": ["chloroform", "oleanene triterpenoid", "H", "(13)C", "terpenoid", "5\u03b1,6\u03b1-dimethoxy-7,11,14-trioxoabieta-8,12-diene", "(1)H", "xantoquinone", "1\u03b2,3\u03b2-dihydroxy-12-oleanene", "abietane diterpenoid"]}