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:

Bioactive phenolics from Seriphidium stenocephalum. Chromatographic separation of the ethyl acetate soluble part of the methanolic extract from Seriphidium stenocephalum yielded three new compounds: stenocepflavone (1), stenocepflavan (2), and stenocephol (3), together with cirsimaritin (4), 5,7,5'-trihydroxy-3',4',6-trimethoxyflavone (5), 5,6,7,5'-tetrahydroxy-4'-methoxyflavone (6), and axillaroside (7). All isolates were characterized with the help of spectroscopic data including 1D, 2D NMR, and high resolution mass spectrometry and/or in comparison with the related compounds in literature. All compounds were tested for in vitro enzyme inhibitory activities against acetylcholinesterase, butyrylcholinesterase, and lipoxygenase. Compounds 1 and 4-7 exhibited significant activity against all the tested enzymes, whereas compounds 2 and 3 were found inactive.
{"Chemical": ["ethyl acetate", "5,6,7,5\u0027-tetrahydroxy-4\u0027-methoxyflavone", "cirsimaritin", "stenocephol", "5,7,5\u0027-trihydroxy-3\u0027,4\u0027,6-trimethoxyflavone", "phenolics", "stenocepflavan", "axillaroside", "stenocepflavone"]}