View source for Chemistry:Diphenylcyclopropenone

{{Chembox
| Name = 
| ImageFile = Diphenylcyclopropenone.svg
| ImageSize = 200px
| PIN = 2,3-Diphenylcycloprop-2-en-1-one
| OtherNames = Diphencyprone, DPCP, DPC
| Section1 = {{Chembox Identifiers
| CASNo = 886-38-4
| CASNo_Ref = {{cascite|correct|CAS}}
| PubChem = 65057
| ChemSpiderID = 58568
| UNII = I7G14NW5EC
| SMILES = O=C2C(=C2\c1ccccc1)\c3ccccc3
| InChI = InChI=1S/C15H10O/c16-15-13(11-7-3-1-4-8-11)14(15)12-9-5-2-6-10-12/h1-10H
  }}
| Section2 = {{Chembox Properties
| C=15 | H=10 | O=1
| Appearance = 
| Density = 
| MeltingPt = 
| BoilingPt = 
| Solubility =
  }}
| Section3 = {{Chembox Hazards
| MainHazards = 
| FlashPt = 
| AutoignitionPt =
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| Section4 = 
| Section5 = 
| Section6 = 
}}

'''Diphenylcyclopropenone''' ('''diphencyprone''') is a topically administered experimental drug intended for treating [[Medicine:Alopecia areata|alopecia areata]] and alopecia totalis.<ref>{{cite journal | vauthors = Singh G, Lavanya M | title = Topical immunotherapy in alopecia areata | journal = International Journal of Trichology | volume = 2 | issue = 1 | pages = 36–9 | date = January 2010 | pmid = 21188022 | pmc = 3002409 | doi = 10.4103/0974-7753.66911 | doi-access = free }}</ref> Topical immunotherapy using diphenylcyclopropenone may also be an effective treatment option for recalcitrant warts.<ref name="Upitis">{{cite journal | vauthors = Upitis JA, Krol A | title = The use of diphenylcyclopropenone in the treatment of recalcitrant warts | journal = Journal of Cutaneous Medicine and Surgery | volume = 6 | issue = 3 | pages = 214–7 | year = 2002 | pmid = 11951129 | doi = 10.1007/s10227-001-0050-9 | s2cid = 38571189 }}</ref>  It is not approved by either the [[Organization:Food and Drug Administration|Food and Drug Administration]] or the [[Organization:European Medicines Agency|European Medicines Agency]].<ref name=":0">{{cite journal | vauthors = Bulock KG, Cardia JP, Pavco PA, Levis WR | title = Diphencyprone Treatment of Alopecia Areata: Postulated Mechanism of Action and Prospects for Therapeutic Synergy with RNA Interference | journal = The Journal of Investigative Dermatology. Symposium Proceedings | volume = 17 | issue = 2 | pages = 16–8 | date = November 2015 | pmid = 26551938 | doi = 10.1038/jidsymp.2015.33 | doi-access = free }}</ref>

==Mechanism of action==
Diphenylcyclopropenone triggers an immune response that is thought to oppose the action of the autoreactive cells that otherwise cause hair loss.<ref>[http://www.ema.europa.eu/docs/en_GB/document_library/Orphan_designation/2009/10/WC500006138.pdf Public summary of positive opinion for orphan designation of diphenylcyclopropenone for the treatment of alopecia totalis], [[Organization:European Medicines Agency|European Medicines Agency]]. Document Date: London, 23 April 2009. Doc.Ref.:EMEA/COMP/428277/2006</ref> One hypothesis is that in response to DPCP treatment, the body will attempt to downregulate inflammation through a variety of pathways, resulting in a downregulation of the autoimmune response at the hair follicle. This autoinflammatory reaction would otherwise destroy body's hair follicles.<ref name=":0" />

==Studies==
A study of 41 alopecia areata patients showed significant hair regrowth in 40% at 6 months, being sustained in two thirds of these after a 12-month-follow up-period.<ref>{{cite journal | vauthors = Sotiriadis D, Patsatsi A, Lazaridou E, Kastanis A, Vakirlis E, Chrysomallis F | title = Topical immunotherapy with diphenylcyclopropenone in the treatment of chronic extensive alopecia areata | journal = Clinical and Experimental Dermatology | volume = 32 | issue = 1 | pages = 48–51 | date = January 2007 | pmid = 17004987 | doi = 10.1111/j.1365-2230.2006.02256.x | s2cid = 43725892 }}</ref>

In a 2002 study for the treatment of warts, the responders consisted of 135 individuals (87.7%) that had complete clearance of warts. Reported adverse effects were local and included with pruritus (itching) (15.6%), with blistering (7.1%), and with eczematous reactions (eczema)(14.2%). The majority of the patients tolerated the treatment very well. One patient developed local impetigo (minor infection). Patients had an average of 5 treatments over a 6-month period.<ref name=Upitis/>

== Chemical properties ==
The chemical properties of diphenylcyclopropenone are dominated by the strong [[Physics:Dielectric|polarization]] of the carbonyl group, which gives a partial positive charge with [[Chemistry:Aromaticity|aromatic stabilization]] on the cyclopropene ring and a partial negative charge on oxygen. Furthermore, the phenyl groups stabilize the partial positive charge in the ring through [[Chemistry:Resonance|resonance]].

Diphenylcyclopropenone reacts with electrophilic chlorinating agents, including [[Chemistry:Oxalyl chloride|oxalyl chloride]], [[Chemistry:Thionyl chloride|thionyl chloride]] and [[Chemistry:Phosphorus pentachloride|phosphorus pentachloride]], to give 3,3-dichloro-1,2-diphenylcyclopropene, which is a reagent for the activation of carboxylic acids.<ref>{{Cite book|last=Bennett|first=Clay S.|chapter=3,3-Dichloro-1,2-diphenylcyclopropene|date=2012|title=[[Chemistry:Encyclopedia of Reagents for Organic Synthesis|Encyclopedia of Reagents for Organic Synthesis]]|publisher=John Wiley & Sons|language=en|doi=10.1002/047084289x.rn01514|isbn=978-0471936237 }}</ref>

== See also ==
* [[Chemistry:Benzophenone|Benzophenone]]
* [[Chemistry:Cyclopropenone|Cyclopropenone]]

== References ==
{{reflist}}

[[Category:Ketones]]
[[Category:Cyclopropenes]]
[[Category:Phenyl compounds]]

{{Sourceattribution|Diphenylcyclopropenone}}