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:

Drug repurposing in pediatrics and pediatric hematology oncology. Drug 'repurposing', that is, using old drugs for new indications, has been proposed as a more efficient strategy for drug development than the current standard of beginning with novel agents. In this review, we explore the scope of drug repurposing in pediatric hematology oncology and in pediatrics in general. Drugs commonly used in children were identified using the Harriet Lane Handbook (HLH) and searched in PubMed for different uses. Additional drugs were identified by searching PubMed and Google.com for 'drug repurposing' or 'drug repositioning'. Almost 10% of drugs with primary uses in pediatrics have been repurposed in pediatric hematology oncology or pediatrics. The observant clinician, pharmacologist and translational bioinformatician, as well as structural targeting, will have a role in discovering new repurposing opportunities.
{"Chemical": []}