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:

Design, synthesis and biological activity of multifunctional α,β-unsaturated carbonyl scaffolds for Alzheimer's disease. A series of compounds containing an α,β-unsaturated carbonyl moiety, such as chalcones and coumarins were designed, synthesized and tested in a variety of assays to assess their potential as anti-Alzheimer's disease (AD) agents. The investigations included the inhibition of cholinesterases (AChE, BuChE), the inhibition of amyloid beta (Aβ) self-assembly and the disassembly of preformed Aβ oligomers. Several compounds showed excellent potential as multifunctional compounds for AD. Docking studies for 16 that performed well in all the assays gave a clear interpretation of various interactions in the gorge of AChE. Based on the results, the long-chain coumarin scaffold appears to be a promising structural template for further AD drug development.
{"Chemical": ["chalcones", "coumarin", "coumarins", "\u03b1,\u03b2-unsaturated carbonyl"]}