Chemistry:Phenidone
Phenidone (1-phenyl-3-pyrazolidinone) is an organic compound that is primarily used as a photographic developer. It has five to ten times the developing power as Metol, capable of achieving the same level of development in both less time and at a lower concentration.[1] It also has low toxicity and unlike some other developers, does not cause dermatitis upon skin contact.[2] As a developer, Phenidone is typically used in conjunction with hydroquinone for black and white photography and performs better at lower pH levels.[3]
Phenidone is Ilford's trademark for this material, which was first filed on Feb. 24, 1953, but has since expired.[4] Although the compound was first prepared in 1890; it was not until 1940 that J. D. Kendall, in the laboratories of Ilford Limited, discovered the reducing properties of this compound. Large scale production did not become feasible until 1951.[5]
Phenidone functions as a reducing agent. It converts to the N-phenyl-hydroxypyrazole. It is oxidized in acidic conditions, contributing the electrons it loses to reduce silver halides such as those found in film:[6]
Phenidone is also a dual cyclooxygenase/lipoxygenase inhibitor, capable of blocking the synthesis of arachidonic acid, which plays a role in causing inflammation in systemic inflammatory response syndrome[7] and neuronal damage in kainic acid-induced seizures.[8]
Preparation
Phenidone can be prepared by heating phenyl hydrazine with 3-chloropropanoic acid.[2]
References
- ↑ Axford, A.J.; Kendall, J.D. (January 1, 1954). "Phenidone—Part 1; The Mechanism of its Developing Action and its Super-additivity with Hydroquinone *" (in en). The Journal of Photographic Science 2 (1): 1–7. doi:10.1080/03700240.1954.11736538. ISSN 0370-0240. http://www.tandfonline.com/doi/full/10.1080/03700240.1954.11736538.
- ↑ 2.0 2.1 Merck Index of Chemicals and Drugs, 9th ed. monograph 7115
- ↑ Mason, L. F. A. (January 1, 1965). "Role of Phenidone in Modern Processing" (in en). The Journal of Photographic Science 13 (4): 205–209. doi:10.1080/00223638.1965.11737306. ISSN 0022-3638. http://www.tandfonline.com/doi/full/10.1080/00223638.1965.11737306.
- ↑ "Trademark Status & Document Retrieval". https://tsdr.uspto.gov/#caseNumber=71642654&caseSearchType=US_APPLICATION&caseType=DEFAULT&searchType=statusSearch.
- ↑ Karlheinz Keller et al. "Photography" in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim. doi: 10.1002/14356007.a20_001
- ↑ Spirin, M. G.; Brichkin, S. B.; Razumov, V. F. (2002). "Phenidone Oxidation during Photoinitiated Chemical Reduction of AgBr Nanocrystals in Water Pools of Reverse Micelles". Colloid Journal 64 (3): 364–368. doi:10.1023/A:1015981028758. http://link.springer.com/10.1023/A:1015981028758.
- ↑ Schroeder, Torsten (March 2008). "Activity of the lipoxygenase inhibitor 1-phenyl-3-pyrazolidinone (phenidone) and derivatives on the inhibition of adhesion molecule expression on human umbilical vascular endothelial cells" (in en). Biologics: Targets and Therapy: 151. doi:10.2147/BTT.S2542. ISSN 1177-5475. PMID 19707438. PMC 2727783. http://www.dovepress.com/activity-of-the-lipoxygenase-inhibitor-1-phenyl-3-pyrazolidinone-pheni-peer-reviewed-article-BTT.
- ↑ Kim, Hyoung-Chun; Jhoo, Wang-Kee; Bing, Guoying; Shin, Eun-Joo; Wie, Myung-Bok; Kim, Won-Ki; Ko, Kwang Ho (August 18, 2000). "Phenidone prevents kainate-induced neurotoxicity via antioxidant mechanisms" (in en). Brain Research 874 (1): 15–23. doi:10.1016/S0006-8993(00)02560-9. https://linkinghub.elsevier.com/retrieve/pii/S0006899300025609.
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