Browse history interactively

Page 1

Page 1Revision 1

Page 2

Page 2Revision 2

← Previous editContent deleted Content addedVisualWikitext

Revision as of 15:13, 26 January 2011 editCheMoBot (talk | contribs)Bots141,565 edits Updating {{chembox}} (no changed fields - added verified revid - updated 'UNII_Ref', 'StdInChIKey_Ref', 'ChEMBL_Ref') per Chem/Drugbox validation (report [[Wikipedia_talk:WikiProject_Chemicals|er← Previous edit		Latest revision as of 11:52, 24 November 2024 edit undoM97uzivatel (talk | contribs)Extended confirmed users6,569 edits →Use and manufacturing
(180 intermediate revisions by more than 100 users not shown)
Line 1:		Line 1:
			{{Distinguish|Xanthene|Xanthan}}
	{{distinguish|xanthene}}
	{{chembox		{{chembox
			| Verifiedfields = changed
	| verifiedrevid = 410176309
			| verifiedrevid = 410178132
	| reference = <ref>''Merck Index'', 11th Edition, '''9968'''.</ref>
			| Reference = <ref>''Merck Index'', 11th Edition, '''9968'''.</ref>
	| ImageFile = Xanthin - Xanthine.svg		| ImageFile = Xanthin - Xanthine.svg
			| ImageClass = skin-invert-image
	| ImageSize =		| ImageSize =
	| ImageFile2 = Xanthine-3D-balls.png		| ImageFile2 = Xanthine-3D-balls.png
	| IUPACName = 3,7-Dihydropurine-2,6-dione		| PIN = 3,7-Dihydro-1''H''-purine-2,6-dione
	| OtherNames = 1''H''-Purine-2,6-diol		| OtherNames = 1''H''-Purine-2,6-dione
	| Section1 = {{Chembox Identifiers		|Section1={{Chembox Identifiers
			| IUPHAR_ligand = 4557
	| Abbreviations =		| Abbreviations =
	| InChI = 1S/C5H4N4O2/c10-4-2-3(7-1-6-2)8-5(11)9-4/h1H,(H3,6,7,8,9,10,11)		| InChI = 1S/C5H4N4O2/c10-4-2-3(7-1-6-2)8-5(11)9-4/h1H,(H3,6,7,8,9,10,11)
Line 14:		Line 17:
	| InChI1 = 1S/C5H4N4O2/c10-4-2-3(7-1-6-2)8-5(11)9-4/h1H,(H3,6,7,8,9,10,11)		| InChI1 = 1S/C5H4N4O2/c10-4-2-3(7-1-6-2)8-5(11)9-4/h1H,(H3,6,7,8,9,10,11)
	| CASNo = 69-89-6		| CASNo = 69-89-6
	| CASNo_Ref = {{cascite|correct|CAS}}= {{cascite|??|??}}		| CASNo_Ref = {{cascite|correct|CAS}}
	| EINECS =		| EINECS =
	| PubChem = 1188		| PubChem = 1188
	| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}		| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
	| ChemSpiderID = 1151		| ChemSpiderID = 1151
			| DrugBank_Ref = {{drugbankcite|changed|drugbank}}
	| SMILES = c1c2c(n1)nc(nc2O)O
			| DrugBank = DB02134
	| ChEMBL_Ref = {{ebicite|correct|EBI}}
			| UNII_Ref = {{fdacite|changed|FDA}}
			| UNII = 1AVZ07U9S7
			| StdInChIKey_Ref = {{stdinchicite|changed|chemspider}}
			| StdInChIKey = LRFVTYWOQMYALW-UHFFFAOYSA-N
			| SMILES = c1c2c(n1)nc(nc2O)O
			| ChEMBL_Ref = {{ebicite|correct|EBI}}
	| ChEMBL = 1424		| ChEMBL = 1424
	| StdInChI_Ref = {{stdinchicite|correct|chemspider}}		| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
			| StdInChI = 1S/C5H4N4O2/c10-4-2-3(7-1-6-2)8-5(11)9-4/h1H,(H3,6,7,8,9,10,11)
	| StdInChI = StdInChI_Ref = {{stdinchicite|correct|chemspider}}
	| StdInChI=1S/C5H4N4O2/c10-4-2-3(7-1-6-2)8-5(11)9-4/h1H,(H3,6,7,8,9,10,11)
	| RTECS =		| RTECS =
	| MeSHName =		| MeSHName =
			| ChEBI_Ref = {{ebicite|changed|EBI}}
	| ChEBI =
			| ChEBI = 17712
	| KEGG_Ref = {{keggcite|correct|kegg}}
			| KEGG_Ref = {{keggcite|changed|kegg}}
	| KEGG =
			| KEGG = C00385
	| ATCCode_prefix =
			}}
	| ATCCode_suffix =
			|Section2={{Chembox Properties
	| ATC_Supplemental =}}
	| Section2 = {{Chembox Properties
	| Formula = C<sub>5</sub>H<sub>4</sub>N<sub>4</sub>O<sub>2</sub>		| Formula = C<sub>5</sub>H<sub>4</sub>N<sub>4</sub>O<sub>2</sub>
	| MolarMass = 152.11 g/mol		| MolarMass = 152.11 g/mol
Line 39:		Line 46:
	| Density =		| Density =
	| MeltingPt = decomposes		| MeltingPt = decomposes
	| Melting_notes =		| MeltingPt_notes =
	| BoilingPt =		| BoilingPt =
	| Boiling_notes =		| BoilingPt_notes =
	| Solubility = 1 g/ 14.5 L @ 16 °C<br>1 g/1.4 L @ 100 °C		| Solubility = 1 g/ 14.5 L @ 16 °C<br>1 g/1.4 L @ 100 °C
	| SolubleOther =		| SolubleOther =
Line 47:		Line 54:
	| pKa =		| pKa =
	| pKb = }}		| pKb = }}
	| Section7 = {{Chembox Hazards		|Section6={{Chembox Pharmacology
	| EUClass =		| ATCCode_prefix =
	| EUIndex =		| ATCCode_suffix =
			| ATC_Supplemental =
			}}
			|Section7={{Chembox Hazards
	| MainHazards =		| MainHazards =
	| NFPA-H =		| NFPA-H = 2
	| NFPA-F =		| NFPA-F = 1
	| NFPA-R =		| NFPA-R = 0
	| NFPA-O =		| NFPA-S =
	| RPhrases =		| HPhrases =
	| SPhrases =		| PPhrases =
	| RSPhrases =		| GHS_ref =
	| FlashPt =		| FlashPt =
	| Autoignition =		| AutoignitionPt =
	| ExploLimits =		| ExploLimits =
	| PEL = }}		| PEL =
			}}
	}}		}}
	'''Xanthine''' ({{pron-en|ˈzænθiːn}} or {{IPA-en|ˈzænθaɪn|}}), (3,7-dihydro-purine-2,6-dione), is a ] ] found in most human body tissues and fluids and in other organisms. A number of mild ]s are derived from xanthine, including ] and ].<ref name="isbn0-8493-2647-8">{{cite book | author = Spiller, Gene A. | authorlink = | editor = | others = | title = Caffeine | edition = | language = | publisher = CRC Press | location = Boca Raton | year = 1998 | origyear = | pages = | quote = | isbn = 0-8493-2647-8 | oclc = | doi = | url = | accessdate = }}</ref>		'''Xanthine''' ({{IPAc-en|ˈ|z|æ|n|θ|iː|n}} or {{IPAc-en|ˈ|z|æ|n|θ|aɪ|n}}, from ] {{Lang|grc|ξανθός}} {{Lang|grc-latn|xanthós}} {{Gloss|yellow}} for its yellowish-white appearance; archaically '''xanthic acid'''; systematic name '''3,7-dihydropurine-2,6-dione''') is a ] ] found in most human body tissues and fluids, as well as in other organisms.<ref name="pubchem">{{cite web |title=Xanthine, CID 1188 |url=https://pubchem.ncbi.nlm.nih.gov/compound/1188 |publisher=PubChem, National Library of Medicine, US National Institutes of Health |access-date=28 September 2019 |date=2019}}</ref> Several ]s are derived from xanthine, including ], ], and ].<ref name="isbn0-8493-2647-8">{{cite book | author = Spiller, Gene A. | title = Caffeine | publisher = CRC Press | location = Boca Raton | year = 1998 | isbn = 0-8493-2647-8 }}</ref><ref name=":0">{{Cite book|last=Katzung|first=Bertram G.|title=Basic & Clinical Pharmacology|publisher=Paramount Publishing|year=1995|isbn=0-8385-0619-4|location=East Norwalk, Connecticut|pages=310, 311}}</ref>
	Xanthine is a product on the pathway of ].		Xanthine is a product on the pathway of ].<ref name=pubchem/>
	* It is created from ] by ].		* It is created from ] by ].
	* It is created from ] by ].		* It is created from ] by ].
			* It is also created from ] by ].
	Xanthine is subsequently converted to ] by the action of the ] enzyme.		Xanthine is subsequently converted to ] by the action of the ] enzyme.<ref name=pubchem/>
			==Use and production==
	==Pathology==
			Xanthine is used as a ] ] for human and animal medications, and is produced as a ] ingredient.<ref name=pubchem/>
	People with the rare ] ] lack sufficient xanthine oxidase and cannot convert xanthine to uric acid.
	==Clinical significance of xanthine derivatives==		==Clinical significance==
	Derivatives of xanthine, known collectively as '''xanthines''', are a group of ]s commonly used for their effects as mild ]s and as ]s, notably in treating the symptoms of ]. In contrast to other, more potent stimulants, they only inhibit the actions of sleepiness-inducing ], making them somewhat less effective as stimulants than ]s. Due to widespread effects, the ] of xanthines is narrow, making them merely a second-line asthma treatment. The therapeutic level is 10-20 micrograms/mL blood; signs of toxicity include tremor, nausea, nervousness, and tachycardia/arrhythmia.		Derivatives of xanthine (known collectively as '''xanthines''') are a group of ]s commonly used for their effects as mild ]s and as ]s, notably in the treatment of ] or ] symptoms.<ref name=pubchem/> In contrast to other, more potent stimulants like ]s, xanthines mainly act to oppose the actions of ], and increase alertness in the ].<ref name=pubchem/>
			===Toxicity===
	Methylxanthines affect not only the airways but stimulate heart rate, force of contraction, cardiac arrhythmias at high concentrations. In the CNS they increase alertness, stimulate the respiratory centre, and are used for treatment of infantile apnea. In high doses they can lead to convulsions that are resistant to anticonvulsants. Methylxanthines induce acid and pepsin secretions in the GI tract.
			'''Methylxanthines''' (] xanthines), which include ], ], ], ], ], ], ], and ] (heteroxanthine), among others, affect the airways, increase heart rate and force of contraction, and at high concentrations can cause cardiac arrhythmias.<ref name=pubchem/> In high doses, they can lead to convulsions that are resistant to anticonvulsants.<ref name=pubchem/> Methylxanthines induce ] and ] secretions in the ].<ref name=pubchem/> Methylxanthines are metabolized by ] in the liver.<ref name=pubchem/>
	Methylxanthines are metabolized by Cytochrome P450 in the liver.
	] xanthines include ], ], ], ], ] <ref name="PTX-Deree">{{cite journal | author=Deree J, Martins JO, Melbostad H, Loomis WH, Coimbra R. | title=Insights into the regulation of TNF-alpha production in human mononuclear cells: the effects of non-specific phosphodiesterase inhibition. | journal=Clinics (Sao Paulo). | year=2008 | pages=321–8 | volume=63 | issue=3 | pmid=18568240 | doi=10.1590/S1807-59322008000300006 | pmc=2664230 }}</ref>, ], and ]. These drugs act as both
	# competitive nonselective ] <ref name="PDEs-Essayan">{{cite journal | author=Essayan DM. | title=Cyclic nucleotide phosphodiesterases. | journal=J Allergy Clin Immunol. | year=2001 | pages=671–80 | volume=108 | issue=5 | pmid=11692087 | doi=10.1067/mai.2001.119555 }}</ref> which raise intracellular ], activate ], ] <ref name="PTX-Deree">{{cite journal | author=Deree J, Martins JO, Melbostad H, Loomis WH, Coimbra R. | title=Insights into the regulation of TNF-alpha production in human mononuclear cells: the effects of non-specific phosphodiesterase inhibition. | journal=Clinics (Sao Paulo). | year=2008 | pages=321–8 | volume=63 | issue=3 | pmid=18568240 | doi=10.1590/S1807-59322008000300006 | pmc=2664230 }}</ref> <ref name="pmid9927365">{{cite journal |author=Marques LJ, Zheng L, Poulakis N, Guzman J, Costabel U |title=Pentoxifylline inhibits TNF-alpha production from human alveolar macrophages |journal=Am. J. Respir. Crit. Care Med. |volume=159 |issue=2 |pages=508–11 |year=1999 |month=February |pmid=9927365 |doi= |url=http://ajrccm.atsjournals.org/cgi/pmidlookup?view=long&pmid=9927365}}</ref> and ] <ref name="LT-Peters-Golden">{{cite journal | author=Peters-Golden M, Canetti C, Mancuso P, Coffey MJ. | title=Leukotrienes: underappreciated mediators of innate immune responses. | journal=J Immunol. | year=2005 | pages=589–94 | volume=174 | issue=2 | pmid=15634873 | url=http://www.jimmunol.org/cgi/content/full/174/2/589 }}</ref> synthesis, and ] and ] <ref name="LT-Peters-Golden">{{cite journal | author=Peters-Golden M, Canetti C, Mancuso P, Coffey MJ. | title=Leukotrienes: underappreciated mediators of innate immune responses. | journal=J Immunol. | year=2005 | pages=589–94 | volume=174 | issue=2 | pmid=15634873 | url=http://www.jimmunol.org/cgi/content/full/174/2/589 }}</ref> and
	# nonselective ] antagonists <ref name="AR-Daly">{{cite journal | author=Daly JW, Jacobson KA, Ukena D. | title=Adenosine receptors: development of selective agonists and antagonists. | journal=Prog Clin Biol Res. | year=1987 | pages=:41–63 | volume=230 | issue=1 | pmid=3588607 }}</ref> which inhibit sleepiness-inducing ].
	But different analogues show varying potency at the numerous subtypes, and a wide range of synthetic xanthines (some nonmethylated) have been developed searching for compounds with greater selectivity for ] or ] subtypes.<ref>MacCorquodale DW. THE SYNTHESIS OF SOME ALKYLXANTHINES. ''Journal of the American Chemical Society''. 1929 July;51(7):2245–2251. DOI: 10.1021/ja01382a042</ref><ref>, Sunshine A, Laska EM, Siegel CE, "ANALGESIC AND ANTI-INFLAMMATORY COMPOSITIONS COMPRISING XANTHINES AND METHODS OF USING SAME", granted 1989-03-22 , assigned to RICHARDSON-VICKS, INC.</ref><ref name="US 4288433">{{Ref patent3 | country = US | number = 4288433 | status = granted | title = Cosmetic compositions having a slimming action | pubdate = 1979-09-24 | gdate = 1981-09-04 | pridate= 1979-09-24 | inventor = Constantin Koulbanis, Claude Bouillon, Patrick Darmenton | assign1= L'Oreal | google_patent_id = 96M6AAAAEBAJ }}</ref><ref name="pmid3806581">{{cite journal | author = Daly JW, Padgett WL, Shamim MT | title = Analogues of caffeine and theophylline: effect of structural alterations on affinity at adenosine receptors | journal = Journal of Medicinal Chemistry | volume = 29 | issue = 7 | pages = 1305–8 | year = 1986 | month = July | pmid = 3806581 | doi = 10.1021/jm00157a035| url = | issn = }}</ref><ref name="pmid3588607">{{cite journal | author = Daly JW, Jacobson KA, Ukena D | title = Adenosine receptors: development of selective agonists and antagonists | journal = Progress in Clinical and Biological Research | volume = 230 | issue = | pages = 41–63 | year = 1987 | pmid = 3588607 | doi = | url = | issn = }}</ref><ref name="pmid2456442">{{cite journal | author = Choi OH, Shamim MT, Padgett WL, Daly JW | title = Caffeine and theophylline analogues: correlation of behavioral effects with activity as adenosine receptor antagonists and as phosphodiesterase inhibitors | journal = Life Sciences | volume = 43 | issue = 5 | pages = 387–98 | year = 1988 | pmid = 2456442 | doi = 10.1016/0024-3205(88)90517-6| url = | issn = }}</ref><ref name="pmid2724296">{{cite journal | author = Shamim MT, Ukena D, Padgett WL, Daly JW | title = Effects of 8-phenyl and 8-cycloalkyl substituents on the activity of mono-, di-, and trisubstituted alkylxanthines with substitution at the 1-, 3-, and 7-positions | journal = Journal of Medicinal Chemistry | volume = 32 | issue = 6 | pages = 1231–7 | year = 1989 | month = June | pmid = 2724296 | doi = 10.1021/jm00126a014| url = | issn = }}</ref><ref name="pmid1658821">{{cite journal | author = Daly JW, Hide I, Müller CE, Shamim M | title = Caffeine analogs: structure-activity relationships at adenosine receptors | journal = Pharmacology | volume = 42 | issue = 6 | pages = 309–21 | year = 1991 | pmid = 1658821 | doi = 10.1159/000138813| url = | issn = }}</ref><ref name="pmid7680859">{{cite journal | author = Ukena D, Schudt C, Sybrecht GW | title = Adenosine receptor-blocking xanthines as inhibitors of phosphodiesterase isozymes | journal = Biochemical Pharmacology | volume = 45 | issue = 4 | pages = 847–51 | year = 1993 | month = February | pmid = 7680859 | doi = 10.1016/0006-2952(93)90168-V| url = http://linkinghub.elsevier.com/retrieve/pii/0006-2952(93)90168-V | issn = }}</ref><ref name="pmid10869699">{{cite journal | author = Daly JW | title = Alkylxanthines as research tools | journal = Journal of the Autonomic Nervous System | volume = 81 | issue = 1-3 | pages = 44–52 | year = 2000 | month = July | pmid = 10869699 | doi = 10.1016/S0165-1838(00)00110-7| url = http://linkinghub.elsevier.com/retrieve/pii/S0165183800001107 | issn = }}</ref><ref name="pmid17514358">{{cite journal | author = Daly JW | title = Caffeine analogs: biomedical impact | journal = Cellular and Molecular Life Sciences : CMLS | volume = 64 | issue = 16 | pages = 2153–69 | year = 2007 | month = August | pmid = 17514358 | doi = 10.1007/s00018-007-7051-9 | url = | issn = }}</ref><ref name="pmid17668454">{{cite journal | author = González MP, Terán C, Teijeira M | title = Search for new antagonist ligands for adenosine receptors from QSAR point of view. How close are we? | journal = Medicinal Research Reviews | volume = 28 | issue = 3 | pages = 329–71 | year = 2008 | month = May | pmid = 17668454 | doi = 10.1002/med.20108 | url = | issn = }}</ref><ref name="pmid18181659">{{cite journal | author = Baraldi PG, Tabrizi MA, Gessi S, Borea PA | title = Adenosine receptor antagonists: translating medicinal chemistry and pharmacology into clinical utility | journal = Chemical Reviews | volume = 108 | issue = 1 | pages = 238–63 | year = 2008 | month = January | pmid = 18181659 | doi = 10.1021/cr0682195 | url = | issn = }}</ref> Xanthines are also found very rarely as constituents of ]s.
			If swallowed, inhaled, or exposed to the eyes in high amounts, xanthines can be harmful, and they may cause an ] if applied ].<ref name=pubchem/>
	]
			===Pharmacology===
			]
			In ] ] studies, xanthines act as both competitive nonselective ] and nonselective ] antagonists. ] raise intracellular ], activate ], ] synthesis,<ref name=pubchem/><ref name="pmid9927365">{{cite journal |vauthors=Marques LJ, Zheng L, Poulakis N, Guzman J, Costabel U |title=Pentoxifylline inhibits TNF-alpha production from human alveolar macrophages |journal=Am. J. Respir. Crit. Care Med. |volume=159 |issue=2 |pages=508–11 |date=February 1999 |pmid=9927365 |doi= 10.1164/ajrccm.159.2.9804085}}</ref><ref name=":0" /> and ]<ref name="LT-Peters-Golden">{{cite journal |vauthors=Peters-Golden M, Canetti C, Mancuso P, Coffey MJ | title=Leukotrienes: underappreciated mediators of innate immune responses | journal=J. Immunol. | year=2005 | pages=589–94 | volume=174 | issue=2 | pmid=15634873 | doi=10.4049/jimmunol.174.2.589| doi-access=free }}</ref> and ] and ].<ref name="LT-Peters-Golden"/> ] antagonists <ref name="AR-Daly">{{cite journal |vauthors=Daly JW, Jacobson KA, Ukena D | title=Adenosine receptors: development of selective agonists and antagonists | journal=Prog Clin Biol Res | year=1987 | pages=41–63 | volume=230 | issue=1 | pmid=3588607 }}</ref> inhibit sleepiness-inducing ].<ref name=pubchem/>
			However, different analogues show varying potency at the numerous subtypes, and a wide range of synthetic xanthines (some nonmethylated) have been developed searching for compounds with greater selectivity for ] or ] subtypes.<ref name=pubchem/><ref name="pmid3806581">{{cite journal |vauthors=Daly JW, Padgett WL, Shamim MT | title = Analogues of caffeine and theophylline: effect of structural alterations on affinity at adenosine receptors | journal = Journal of Medicinal Chemistry | volume = 29 | issue = 7 | pages = 1305–8 |date=July 1986 | pmid = 3806581 | doi = 10.1021/jm00157a035}}</ref><ref name="pmid3588607">{{cite journal |vauthors=Daly JW, Jacobson KA, Ukena D | title = Adenosine receptors: development of selective agonists and antagonists | journal = Progress in Clinical and Biological Research | volume = 230 | pages = 41–63 | year = 1987 | pmid = 3588607 }}</ref><ref name="pmid1658821">{{cite journal |vauthors=Daly JW, Hide I, Müller CE, Shamim M | title = Caffeine analogs: structure-activity relationships at adenosine receptors | journal = Pharmacology | volume = 42 | issue = 6 | pages = 309–21 | year = 1991 | pmid = 1658821 | doi = 10.1159/000138813| url = https://zenodo.org/record/1235428}}</ref><ref name="pmid17668454">{{cite journal |vauthors=González MP, Terán C, Teijeira M | title = Search for new antagonist ligands for adenosine receptors from QSAR point of view. How close are we? | journal = Medicinal Research Reviews | volume = 28 | issue = 3 | pages = 329–71 |date=May 2008 | pmid = 17668454 | doi = 10.1002/med.20108 | s2cid = 23923058 }}</ref><ref name="pmid18181659">{{cite journal |vauthors=Baraldi PG, Tabrizi MA, Gessi S, Borea PA | title = Adenosine receptor antagonists: translating medicinal chemistry and pharmacology into clinical utility | journal = Chemical Reviews | volume = 108 | issue = 1 | pages = 238–63 |date=January 2008 | pmid = 18181659 | doi = 10.1021/cr0682195 }}</ref>
	{{-}}
	{| class="wikitable sortable"		{| class="wikitable sortable"
			|+ Examples of xanthine derivatives
	|+ Selected Xanthines
	!Name!!R<sub>1</sub>!!R<sub>2</sub>!!R<sub>3</sub>!!]!!Found In		!Name!!R<sub>1</sub>!!R<sub>2</sub>!!R<sub>3</sub>!!R<sub>8</sub>!!]!!Found in
	|-		|-
			| Xanthine||H||H||H||H||3,7-Dihydro-purine-2,6-dione||Plants, animals
	|]||]||]||]||1,3,7-trimethyl-1H-purine-2,6(3H,7H)-dione||], ], ], ], ]
	|-		|-
	|]||H||]||]||3,7-dihydro-3,7-dimethyl-1H-purine-2,6-dione||], ]		| ]||H||H||]||H||7-methyl-3''H''-purine-2,6-dione||Metabolite of caffeine and theobromine
	|-		|-
	|]||]||]||H||1,3-dimethyl-7H-purine-2,6-dione||], ], ]		| ]||H||CH<sub>3</sub>||CH<sub>3</sub>||H||3,7-Dihydro-3,7-dimethyl-1''H''-purine-2,6-dione||] (]), ], ], ]
	|-		|-
			| ]||CH<sub>3</sub>||CH<sub>3</sub>||H||H||1,3-Dimethyl-7''H''-purine-2,6-dione||], ] (]), ], ]
	|Xanthine||H||H||H||3,7-dihydro-purine-2,6-dione||plants, animals
			|-
			| ]||CH<sub>3</sub>||H||CH<sub>3</sub>||H||1,7-Dimethyl-7''H''-purine-2,6-dione||Animals that have consumed caffeine
			|-
			| ]||CH<sub>3</sub>||CH<sub>3</sub>||CH<sub>3</sub>||H||1,3,7-Trimethyl-1''H''-purine-2,6(3''H'',7''H'')-dione||], ], ], ], ], ], ] (])
			|-
			| ]||CH<sub>3</sub>||CH<sub>3</sub>||H||]|| 8-Chloro-1,3-dimethyl-7''H''-purine-2,6-dione
			| Synthetic pharmaceutical ingredient
			|-
			| ]||CH<sub>3</sub>||CH<sub>3</sub>||H||]|| 8-Bromo-1,3-dimethyl-7''H''-purine-2,6-dione
			| ] diuretic medication
			|-
			|]
			|CH<sub>3</sub>
			|CH<sub>3</sub>
			|C<sub>3</sub>H<sub>7</sub>O<sub>2</sub>
			|H
			|7-(2,3-Dihydroxypropyl)-1,3-dimethyl-3,7-dihydro-1''H''-purine-2,6-dione
			|Synthetic pharmaceutical ingredient
			|-
			|]
			|CH<sub>3</sub>
			|]
			|H
			|H
			|1-Methyl-3-(2-methylpropyl)-7''H''-purine-2,6-dione
			|
			|-
			|]
			|H
			|H
			|H
			|O
			|7,9-Dihydro-1''H''-purine-2,6,8(3''H'')-trione
			|Byproduct of ] nucleotides metabolism and a normal component of urine
	|}		|}
	{{-}}		{{Clear}}
			===Pathology===
			People with rare ]s, specifically ] and ], lack sufficient xanthine oxidase and cannot convert xanthine to ].<ref name=pubchem/>
			==Possible formation in absence of life==
			Studies reported in 2008, based on <sup>12</sup>C/<sup>13</sup>C ]s of ] found in the ], suggested that xanthine and related chemicals, including the ] component ], have been formed ].<ref name="Murch_base">{{Cite journal | last1 = Martins | first1 = Z. | last2 = Botta | first2 = O. | last3 = Fogel | first3 = M. L. | last4 = Sephton | first4 = M. A. | last5 = Glavin | first5 = D. P. | last6 = Watson | first6 = J. S. | last7 = Dworkin | first7 = J. P. | last8 = Schwartz | first8 = A. W. | last9 = Ehrenfreund | first9 = P. | title = Extraterrestrial nucleobases in the Murchison meteorite | doi = 10.1016/j.epsl.2008.03.026 | journal = Earth and Planetary Science Letters | volume = 270 | issue = 1–2 | pages=130–136 | year = 2008 | bibcode=2008E&PSL.270..130M|arxiv = 0806.2286 | s2cid = 14309508 }}</ref><ref>{{Cite web|author=] Staff |title=We may all be space aliens: study |date=13 June 2008 |url=http://afp.google.com/article/ALeqM5j_QHxWNRNdiW35Qr00L8CkwcXyvw |publisher=] |access-date=2011-08-14 |url-status=dead |archive-url=https://web.archive.org/web/20080617213441/http://afp.google.com/article/ALeqM5j_QHxWNRNdiW35Qr00L8CkwcXyvw |archive-date=June 17, 2008 }}</ref> In August 2011, a report, based on ] studies with ] found on Earth, was published suggesting xanthine and related organic molecules, including the ] and ] components ] and ], were found in ].<ref name="Callahan">{{Cite journal | last1 = Callahan | first1 = M. P. | last2 = Smith | first2 = K. E. | last3 = Cleaves | first3 = H. J. | last4 = Ruzicka | first4 = J. | last5 = Stern | first5 = J. C. | last6 = Glavin | first6 = D. P. | last7 = House | first7 = C. H. | last8 = Dworkin | first8 = J. P. | doi = 10.1073/pnas.1106493108 | title = Carbonaceous meteorites contain a wide range of extraterrestrial nucleobases | journal = Proceedings of the National Academy of Sciences | volume = 108 | issue = 34 | pages = 13995–8 | year = 2011 | pmid = 21836052| pmc = 3161613| bibcode = 2011PNAS..10813995C | doi-access = free }}</ref><ref name="Steigerwald">{{cite web |last=Steigerwald |first=John |title=NASA Researchers: DNA Building Blocks Can Be Made in Space |url=http://www.nasa.gov/topics/solarsystem/features/dna-meteorites.html |publisher=] |date=8 August 2011 |access-date=2011-08-10 }}</ref><ref name="DNA">{{cite web |author=ScienceDaily Staff |title=DNA Building Blocks Can Be Made in Space, NASA Evidence Suggests |url=https://www.sciencedaily.com/releases/2011/08/110808220659.htm |date=9 August 2011 |website=] |access-date=2011-08-09}}</ref>
	==See also==		== See also ==
			* ]
	* ]		* ]
			* ]
	* ]		* ]
	* ]
	* ]		* ]
			* ]
	==References==
			* ]
	{{Reflist|colwidth=30em}}
			==References==
			{{Reflist}}
			{{Stimulants}}
	{{Psychostimulants, agents used for ADHD and nootropics}}
	{{Asthma and copd rx}}		{{Asthma and copd rx}}
	{{Nucleotide metabolism intermediates}}		{{Nucleotide metabolism intermediates}}
Line 116:		Line 173:
	]		]
			]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]