In this task, you are given a set of context paragraph and some supporting facts to answer a question. Your task is to generate answer for given question based on set of context paragraphs and supporting facts.
Q: Context_1 : Didesmethylcitalopram is an active metabolite of the antidepressant drug citalopram (racemic). Didesmethyl"es"citalopram is an active metabolite of the antidepressant escitalopram, the "S"-enantiomer of citalopram. Like citalopram and escitalopram, didesmethyl(es)citalopram functions as a selective serotonin reuptake inhibitor (SSRI), and is responsible for some of its parents' therapeutic benefits. Context_2 : Benzimidazole is a heterocyclic aromatic organic compound. This bicyclic compound consists of the fusion of benzene and imidazole. It is a colorless solid. Context_3 : Quinoline is a heterocyclic aromatic organic compound with the chemical formula CHN. It is a colorless hygroscopic liquid with a strong odor. Aged samples, especially if exposed to light, become yellow and later brown. Quinoline is only slightly soluble in cold water but dissolves readily in hot water and most organic solvents. Quinoline itself has few applications, but many of its derivatives are useful in diverse applications. A prominent example is quinine, an alkaloid found in plants. 4-Hydroxy-2-alkylquinolines (HAQs) are involved in antibiotic resistance. Context_4 : Phthalane is a bicyclic aromatic organic compound. It is also known as isocoumaran, or 1,3-dihydro-2-benzofuran. Derivatives are found in the drug Citalopram, and drug candidate Lu 10-171. It can be oxidised to phthalic acid. Context_5 : Isoquinoline is a heterocyclic aromatic organic compound. It is a structural isomer of quinoline. Isoquinoline and quinoline are benzopyridines, which are composed of a benzene ring fused to a pyridine ring. In a broader sense, the term isoquinoline is used to make reference to isoquinoline derivatives. 1-Benzylisoquinoline is the structural backbone in naturally occurring alkaloids including papaverine. The isoquinoline ring in these natural compound derives from the aromatic amino acid tyrosine. Context_6 : Furazan, or 1,2,5-oxadiazole, is an heterocyclic aromatic organic compound consisting of a five-atom ring containing 1 oxygen and 2 nitrogen atoms. The furazan ring system is also found in the steroid furazabol. Furazan and its derivatives are obtained from the oxime derivatives of 1,2-diketones. Context_7 : Hydroquinone, also benzene-1,4-diol or quinol, is an aromatic organic compound that is a type of phenol, a derivative of benzene, having the chemical formula CH(OH). It has two hydroxyl groups bonded to a benzene ring in a "para" position. It is a white granular solid. Substituted derivatives of this parent compound are also referred to as hydroquinones. The name "hydroquinone" was coined by Friedrich Wohler in 1843. Context_8 : Citalopram (brand names: Celexa, Cipramil and others) is an antidepressant drug of the selective serotonin reuptake inhibitor (SSRI) class. It has U.S. Food and Drug Administration approval to treat major depression, which it received in 1998, and is prescribed off-label for other conditions. In Australia, the UK, Germany, Portugal, Poland, and most European countries, it is licensed for depressive episodes and panic disorder with or without agoraphobia. In Spain and Denmark it is also used for obsessivecompulsive disorder. Context_9 : Indazole, also called isoindazole, is a heterocyclic aromatic organic compound. This bicyclic compound consists of the fusion of benzene and pyrazole. Context_10 : Quinazoline is a organic compound with the formula CHN. It is an aromatic heterocycle with a bicyclic structure consisting of two fused six-membered aromatic rings, a benzene ring and a pyrimidine ring. It is a light yellow crystalline solid that is soluble in water. Also known as 1,3-diazanaphthalene, quinazoline received its name from being an aza derivative of quinoline. Though the parent quinazoline molecule is rarely mentioned by itself in technical literature, substituted derivatives have been synthesized for medicinal purposes such as antimalarial and anticancer agents. Quinazoline is a planar molecule. It is isomeric with the other diazanaphthalenes of the benzodiazine subgroup: cinnoline, quinoxaline, and phthalazine. fact_1 : Phthalane is a bicyclic aromatic organic compound. fact_2 : Derivatives are found in the drug Citalopram, and drug candidate Lu 10-171. fact_3 : Citalopram (brand names: Celexa, Cipramil and others) is an antidepressant drug of the selective serotonin reuptake inhibitor (SSRI) class. Question: Derivatives of Phthalane, a bicyclic aromatic organic compound, are found in the drug Citalopram, which is what type of drug?
A:
an antidepressant