Lihat sumber bagi Urasil

{{chembox|Verifiedfields=changed|Watchedfields=changed|verifiedrevid=418274850|Name=Uracil|ImageFile=Uracil.svg|ImageSize=120px|ImageName=Structural formula of uracil|ImageFileL1=Uracil-3D-balls.png|ImageNameL1=Ball-and-stick model of uracil|ImageFileR1=Uracil-3D-vdW.png|ImageNameR1=Space-filling model of uracil|IUPACName=Pirimidina-2,4(1''H'',3''H'')-diona|Section1={{Chembox Identifiers
| IUPHAR_ligand = 4560
| UNII_Ref = {{fdacite|changed|FDA}}
| UNII = 56HH86ZVCT
| SMILES = O=C1NC=CC(=O)N1
| CASNo = 66-22-8
| CASNo_Ref = {{cascite|correct|CAS}}
| ChEBI_Ref = {{ebicite|changed|EBI}} 
| ChEBI = 17568
| ChEMBL_Ref = {{ebicite|changed|EBI}}
| ChEMBL = 566
| PubChem = 1174
| EC_number = 200-621-9
| DrugBank = DB03419
| KEGG = C00106
| 3DMet = B00026
| ChemSpiderID_Ref = {{chemspidercite|changed|chemspider}}
| ChemSpiderID = 1141
| InChI = 1/C4H4N2O2/c7-3-1-2-5-4(8)6-3/h1-2H,(H2,5,6,7,8)
| InChIKey = ISAKRJDGNUQOIC-UHFFFAOYAV
| StdInChI_Ref = {{stdinchicite|changed|chemspider}}
| StdInChI = 1S/C4H4N2O2/c7-3-1-2-5-4(8)6-3/h1-2H,(H2,5,6,7,8)
| StdInChIKey_Ref = {{stdinchicite|changed|chemspider}}
| StdInChIKey = ISAKRJDGNUQOIC-UHFFFAOYSA-N
| RTECS = YQ8650000
| Beilstein = 606623 
| Gmelin = 2896
  }}|Section2={{Chembox Properties
| Formula = C<sub>4</sub>H<sub>4</sub>N<sub>2</sub>O<sub>2</sub>
| MolarMass = 112.08676 g/mol
| Appearance = Pepejal
| Density = 1.32 g/cm<sup>3</sup>
| Solubility = Larut
| MeltingPtC = 335
| MeltingPt_ref = <ref>{{cite book |author1=Myers, Richard L. |author2=Myers, Rusty L. |title=The 100&nbsp;Most Important Chemical Compounds |pages=92–93 |url=https://books.google.com/?id=a4DuGVwyN6cC&pg=PA92&lpg=PA92&dq=Uracil+boiling+point#PPA92,M1|isbn=9780313337581 |year=2007 }}{{full citation needed|date=December 2018}}</ref>
| BoilingPt = N/A – Terurai
  }}|Section7={{Chembox Hazards
| MainHazards = [[Karsinogen]] dan [[teratogen]] dalam pendedahan melampau
| NFPA-H = 1 
| NFPA-F = 1 
| NFPA-R =
| FlashPt = Tidak mudah terbakar
| GHSPictograms = {{GHS07}}{{GHS08}}
| GHSSignalWord = Warning
| HPhrases = {{H-phrases|315|319|335|361}}
| PPhrases = {{P-phrases|201|202|261|264|271|280|281|302+352|304+340|305+351+338|308+313|312|321|332+313|337+313|362|403+233|405|501}}
  }}|Section8={{Chembox Related
| OtherCompounds = [[Timina]] <br> [[Sitosina]]
  }}}}

'''Urasil''' ('''U''') merupakan salah satu daripada bes nitrogen dalam [[asid nukleik]] [[RNA]] bersama [[adenina]] (A), [[guanina]] (G) dan [[sitosina]] (C). Dalam [[DNA]], urasil digantikan dengan [[timina]] (T) yang merupakan sebatian dengan struktur sama tanpa [[Kumpulan metil|metil]]. Urasil merupakan sebatian [[pirimidina]] yang biasa dan mudah dijumpai dalam alam sekitar.<ref name="Garrett1">{{cite book|title=Principals of Biochemistry with a Human Focus|author1=Garrett, Reginald H.|author2=Grisham, Charles M.|publisher=Brooks/Cole Thomson Learning|year=1997|location=United States}}</ref>

== Sintesis ==

Pelbagai tindak balas boleh dilakukan di makmal untuk menghasilkan urasil. Salah satu daripadanya ialah tindak balas antara [[sitosina]] dan air untuk menghasilkan urasil dan [[ammonia]] sebagai bahan sampingan.<ref name="Garrett1" />

<chem>C4H5N3O + H2O -> C4H4N2O2 + NH3</chem>

== Rujukan ==
{{Reflist}}

{{Kawalan kewibawaan}}

[[Kategori:Pirimidina]]