C3H3NO2Diketopiperazine: A diketopiperazine (DKP), also known as a dioxopiperazine or piperazinedione, is a class of organic molecules in which the two nitrogen atoms of a piperazine 6-membered ring are part of amide linkages. There are three regioisomers possible, differing in the locations of the two carbonyl groups around the ring.Fischer oxazole synthesis: The Fischer oxazole synthesis is a chemical synthesis of an oxazole from a cyanohydrin and an aldehyde in the presence of anhydrous hydrochloric acid.Wiley, R.Crystal earpiece: A crystal earpiece, is a type of piezoelectric earphone, producing sound by using a piezoelectric crystal, a material that changes its shape when electricity is applied to it. It is usually designed to plug into the ear canal of the user.HymenolepiasisHapten: Haptens are small molecules that elicit an immune response only when attached to a large carrier such as a protein; the carrier may be one that also does not elicit an immune response by itself. (In general, only large molecules, infectious agents, or insoluble foreign matter can elicit an immune response in the body.Hymenolepis diminuta: Hymenolepis diminuta, also known as rat tapeworm, is a species of Hymenolepis tapeworm that causes hymenolepiasis. It has slightly bigger eggs and proglottids than H.Trimellitic anhydride chlorideFluorobenzenePreauricular sinus and cystContact dermatitisDrug eruptionNitrogen-13: Nitrogen-13 is a radioisotope of nitrogen used in positron emission tomography (PET). It has a half life of a little under ten minutes, so it must be made at the PET site.