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:

Molecular design, synthesis and biological evaluation of cyclic imides bearing benzenesulfonamide fragment as potential COX-2 inhibitors. Part 2. A group of cyclic imides (1-10) was designed for evaluation as a selective COX-2 inhibitors and investigated in vivo for their anti-inflammatory activity. Compounds 6a, 6b, 8a, 8b, 9a, 9b, 10a and 10b were proved to be potent COX-2 inhibitors with IC50 range of 0.1-4.0μM. In vitro COX-1/COX-2 inhibition structure-activity studies identified compound 8a as a highly potent (IC50=0.1μM), and an extremely selective [COX-2 (SI)>1000] comparable to celecoxib [COX-2 (SI)>384], COX-2 inhibitor that showed superior anti-inflammatory activity (ED50=72.4mg/kg) relative to diclofenac (ED50=114mg/kg). Molecular modeling was carried out through docking the designed compounds into the COX-2 binding site to predict if these compounds have analogous binding mode to the COX-2 inhibitors. The study showed that the homosulfonamide fragment of 8a inserted deep inside the 2°-pocket of the COX-2 active site, where the SO2NH2 group underwent H-bonding interaction with Gln(192)(2.95Å), Phe(518)(2.82Å) and Arg(513)(2.63 and 2.73Å). Docking study of the synthesized compound 8a into the active site of COX-2 revealed a similar binding mode to SC-558, a selective COX-2 inhibitor.
{"Chemical": ["Arg", "Gln", "cyclic imides", "SC-558", "celecoxib", "benzenesulfonamide", "diclofenac", "SO2NH2", "Phe", "H", "homosulfonamide"]}