List of chemical compounds with unusual names


List of chemical compounds with unusual names

Chemical nomenclature, replete as it is with compounds with complex names, is a repository for some very peculiar and sometimes startling names. A browse through the Physical Constants of Organic Compounds in the CRC Handbook of Chemistry and Physics (a fundamental resource) will reveal not just the whimsical work of chemists, but the sometimes peculiar compound names that occur as the consequence of simple juxtaposition. Some names derive legitimately from their chemical makeup, from the geographic region where they may be found, the plant or animal species from which they are isolated or the name of the discoverer.

Some are given intentionally unusual trivial names based on their structure, a notable property or at the whim of those who first isolate them. However, many trivial names predate formal naming conventions. Trivial names can also be ambiguous or carry different meanings in different industries, geographic regions and languages.

Godly noted that "Trivial names having the status of INN or ISO are carefully tailor-made for their field of use and are internationally accepted".[1] In his preface to Chemical Nomenclature, Thurlow wrote that "Chemical names do not have to be deadly serious".[2] A classic website in existence since 1997[3] and maintained at the University of Bristol lists a selection of molecules with silly or unusual names strictly for entertainment. These so-called silly or funny trivial names (of course depending on culture) can also serve an educational purpose. In an article in the Journal of Chemical Education, Dennis Ryan argues that students of organic nomenclature (considered a dry and boring subject) may actually take an interest in it when tasked with the job of converting funny-sounding chemical trivial names to their proper systematic names.[4]

The collection listed below presents a sample of trivial names and gives an idea how chemists are inspired when they coin a brand new name for a chemical compound outside of systematic naming. It also includes some examples of systematic names and acronyms that accidentally resemble English words.

Contents

Elements

Glenn Seaborg proposed the chemical symbol Pu (from P.U.) for plutonium as a joke, only to find it officially adopted.[citation needed] Unununium (Uuu) was the former temporary name of the chemical element number 111, a synthetic transuranium element. This element was named roentgenium (Rg) in November 2004.

List of compounds

Adamantane
Adamantane
(tricyclo[3.3.1.13,7]decane), a crystalline cycloalkane,[5][6] an isomer of twistane.
Alcindoromycine an anthracycline antibiotic agent named after the character Alcindoro in La Bohème.[7]
Angelic acid
Angelic acid
An organic acid found in garden angelica (Angelica archangelica), Umbelliferae, and many other plants.
Arsole
Arsole
(C4H5As), an analogue of pyrrole in which an arsenic atom replaces the nitrogen atom.[8] The aromaticity of arsoles has been debated for many years.[9] The compound in which a benzene ring is fused to arsole — typically on the carbon atoms 3 and 4 — is known as benzarsole.
BARF
BARF
(tetrakis[3,5-bis(trifluoromethyl)phenyl]borate), a fluoroaryl borate B(Ar(CF3)2)4, used as a non-coordinating anion
Barrelene
Barrelene
(C8H8), the name derives from the resemblance with a barrel.[10]
Basketane
Basketane
pentacyclo[4.4.0.02,5.03,8.04,7]decane (C10H12), a polycyclic alkane with a structure similar to a basket.
Bastardane a close relative to adamantane and its proper name is ethano-bridged noradamantane. Because its unusual ethano-bridge was a deviation from the standard hydrocarbon caged rearrangements, it came to be known as bastardane—the unwanted child.[11]
Bohemamine an anti-tumour agent named after the Puccini opera La Bohème.[7]
Bongkrek acid
Bongkrek acid
a deadly respiratory toxin named after the fermented coconut dish tempe bongkrèk in which it occurs after contamination with the bacterium Burkholderia cocovenenans. Its name resembles a combination of Bong, Crack and Acid.
Borneol
Borneol
Named after the island Borneo.
Buckminsterfullerene
Fullerene
or buckyballs, a form of carbon named after Buckminster Fuller due to its resemblance to Fuller's geodesic domes. The term was coined by Harold Kroto.[12] The alternative name Footballene was coined by A.D.J. Haymet[13] because the molecule also resembles a football.
Bullvalene
Bullvalene C10H10
tricyclo[3.3.2.02,8]deca-3,6,9-triene (C10H10), was named by organic chemist Maitland Jones, Jr. for William "Bull" Doering who predicted its properties in 1963.[14][15] Within a specific temperature range the molecule is subject to rapid degenerate Cope rearrangements with the result that all carbon atoms and hydrogen atoms are equivalent and that none of the carbon-carbon bonds is permanent.
Cadaverine
Cadaverine
a foul-smelling diamine produced by putrefaction of dead animal tissue.[16]
catP the name of the enzyme responsible for chloramphenicol resistance in various species of bacteria.
Collinemycin an anthracycline antibiotic agent named after the character Colline in La Bohème.[7]
Constipatic acid
Constipatic acid
[2-(14-hydroxypentadecyl)-4-methyl-5-oxo-2,5-dihydrofuran-3-carboxylic acid], an aliphatic acid derived from the Australian Xanthoparmelia lichen.[17]
Crapinon an anticholinergic drug, one side effect of which is constipation
Cubane
Cubane
a hydrocarbon whose eight carbon atoms occupy the vertices of a cube.[18]
Cumene
Cumene
The common name for isopropylbenzene.
Cummingtonite ((Mg,Fe)7Si8(OH)22), a magnesium-iron silicate hydroxide, first identified in Cummington, Massachusetts.
DAMN
DAMN Structure.png
Diaminomaleonitrile, an organic chemical that contains two amine groups and two nitrile groups boud to an ethylene backbone.
Diabolic acid a series of long-chain dicarboxylic acids with chains of different lengths. Named after the Greek word diabollo meaning to mislead.[19]
DEAD
DEAD
an apt acronym, given that diethyl azodicarboxylate is explosive; shock sensitive; carcinogenic; and an eye, skin, and respiratory irritant.
Dickite (Al2Si2O5(OH)4), a clay-like material with a number of manufacturing uses, one of which is as a coating for high-quality bond paper. It is named after its discoverer, Dr. W. Thomas Dick.
Dinocap
Dinocap
(C18H24N2O6), a miticide and contact fungicide used to control powdery mildew in crops.
Draculin
Draculin
an anticoagulant found in the saliva of vampire bats.[20]
DuPhos
DuPhos
A class of asymmetric ligands for asymmetric synthesis. The name DuPhos is derived from the chemical company that developed this type of ligand (DuP , DuPont) and the compound class of phospholanes (Phos) it belongs to.
Earthcide or Fartox (C6Cl5NO2) Also called 'Quintozene, some of the many names for pentachloronitrobenzene, a fungicide.[21]
Fenestrane
Fenestranes
a class of compounds with a 'window pane motif' (the name fenestrane derives from the Latin word fenestra, meaning window), comprising four fused carbocycles centred on a quaternary carbon resulting a twice over spiro compound. The illustration at right shows a generic fenestrane as well as the specific examples [4,4,4,4]fenestrane and [5,5,5,5]fenestrane. Fenestranes are of considerable interest in theoretical chemistry though comparatively few have actually been synthesised.
Fucitol
L-Fucitol
(C6H14O5), an alcohol derived from Fucus vesiculosis, a North Atlantic seaweed. Its optical isomers are also called D-fuc-ol and L-fuc-ol.
fucK the name of the gene that encodes L-fuculokinase, an enzyme that catalyzes a chemical reaction between L-fuculose, ADP, and L-fuculose-1-phosphate.
Furfural
Furfural
Furfural is an industrial chemical compound derived from a variety of agricultural byproducts, including corncobs, oat and wheat bran, and sawdust. The name furfural comes from the Latin word furfur, meaning bran, referring to its usual source.
Fluoboric Acid
Fluoboric acid
BF4H, tetrafluoroborate or tetrafluoroboric acid.
Fukalite (Ca4Si2O6(CO3)(OH, F))2, a rare form of calcium silicocarbonate mined in the Fuka region of Japan.
Gossypol
Gossypol
a toxin found in cottonseed used as a male contraceptive.
Hirsutene
Hirsutene
[22][23] is also named after an animal: a goat (Hircus), occasionally the molecule is depicted upside down[24][25]
Homocubane An molecule synthesized from cubane.
Horseradish peroxidase An enzyme used extensively in molecular biology applications primarily for its ability to amplify a weak signal and increase detectability of a target molecule.
Irene Hantzsch-Widman nomenclature for a monocyclic, heterocyclic compound with three ring atoms.[26]
Josiphos A well-known catalyst, named after Josi Puleo, the technician who first prepared it.[27] Mandyphos and Taniaphos also exist.
Ladderane
Pentacycloanammoxic Acid
An organic molecule that looks like a ladder because it contains two or more fused rings of cyclobutane.
Megaphone a ketone derived from the root of Aniba megaphylla.[28]
Mimimycin an anthracycline antibiotic agent named after the character Mimì in La Bohème.[7]
Miraculin a glycoprotein found in Miracle Fruit that makes sour foods taste sweet after contact with taste buds.[29]
Moronic acid
Moronic acid
3-oxoolean-18-en-28-oic acid, a natural triterpene
Mucic acid
Mucic acid
a product of nitric acid oxidation of galactose or galactose-containing compounds
Muscovite
Muscovite crystals
a phyllosilicate mineral of aluminium and potassium.
Musettamycin an anthracycline antibiotic agent named after the character Musetta in La Bohème.[7]
Naftazone (C11H9N3O2), a vasoprotective drug. The NAFTA free-trade zone is the area covered by the North American Free Trade Agreement.[30]
Nonanal
Nonanal
(C9H18O), an aldehyde derived from nonane.
Olympiadane
Olympiadane
A mechanically-interlocked compound based on the topology for the Olympic rings.
Orotic acid
Orotic acid
(pyrimidinecarboxylic acid), has been referred to as vitamin B13.
PEPPSI PEPPSI is short for Pyridine-Enhanced Precatalyst Preparation Stabilization and Initiation.[31]
Performic acid a strongly oxidizing acid related to formic acid.
Periodic acid
Periodic acid
or per-iodic acid is pronounced /ˌpɜr.aɪˈɒdɨk/ purr-eye-od-ik and not /ˌpɪərɪˈɒdɨk/ peer-ee-od-ik. It refers to one of the two interconvertible species HIO4 (metaperiodic acid) or H5IO6 (orthoperiodic acid - illustrated at right). The per- prefix in the name denotes that iodine is present in its highest possible (+VII) oxidation state.
Periplanone B
Periplanone B
A pheromone of the female American cockroach. Named after the scientific name of this species, Periplaneta americana, not because of periplanarity.
Picket Fence Porphyrin 5,10,15,20-tetrakis(alpha,alpha,alpha-2-pivalamidophenyl)porphyrin, used to model heme enzyme active sites.
Pikachurin a retinal protein named after Pokémon character / species Pikachu
Prismane
Prismane
an isomer of benzene with the carbon atoms arranged in the shape of a triangular prism.
Psicose
Psicose
(C6H12O6), a rare low-calorie sugar that provides 0.3% as much energy as sucrose.
Putrescine
Putrescine
a foul-smelling diamine produced by the putrefaction of dead animal tissue.
Quadratic acid
Squaric acid
a square-shaped organic compound, also called squaric acid.
R-CMP (R-cytodine monophosphate) a component of RNA, but also the acronym for the Royal Canadian Mounted Police.
Ranasmurfin a blue protein from the foam nests of a tropical frog, named after the Smurfs.
Rednose a sugar derived from the degradation of rudolphomycin.[7]
Rhamnetin
Rhamnetin
a flavonol dye derived from buckthorn (rhamnus).[32]
Rhamnose
Rhamnose
a sugar naturally occurring in buckthorn (rhamnus).
Rudolphomycin an anthracycline antibiotic agent named after the character Rodolfo (Rudolph) in La Bohème.[7][33]
Ru(Tris)BiPy-on-a-stick shorthand form of (trans-1,4-bis[(4-pyridyl)ethenyl]benzene)(2,2'-bipyridine)ruthenium(II).[34]
SEX An abbreviation of sodium ethyl xanthate,[35] it has structural formula CH3CH2OCS2Na, IUPAC name sodium O-ethylcarbonodithioate, and it is a flotation agent used in the mining industry;
Skatole
Skatole
a substance of disagreeable odor that occurs in feces, but also in lower concentrations in flowers, orange blossoms, jasmine.
Sonic hedgehog a protein named after Sonic the Hedgehog
Spermine, Spermidine, polyamine
Spermine
Spermidine
growth factors involved in cellular metabolism.
Thebacon
Thebacon
Dihydrocodeinone enol acetate, an opioid analgesic or antitussive.
Titanic acid the hydrated form of titanium dioxide.
Traumatic acid
Traumatic acid
a substance occurring in plants, with a role in healing damaged tissue.
Uranate the chemical term for an oxide anion of the element uranium.
Uranocene
Uranocene
U(C8H8)2, a uranium sandwich compound similar to ferrocene (Fe(C5H5)2) with two co-ordinating aromatic and anionic cyclooctatetraenide rings sandwiching the U atom (formally in its +IV oxidation state).
Vomitoxin
Vomitoxin
a mycotoxine occurring in grains.

See also

Footnotes

  1. ^ Godly, E.W. (1998). Chemical Nomenclature. Kluwer Academic Publishers. pp. 20. ISBN 0751404756. 
  2. ^ Thurlow, Kevin (1998). Chemical Nomenclature. Kluwer Academic Publishers. xii. ISBN 0751404756. 
  3. ^ A more extensive list held at Bristol University
  4. ^ Dennis, Ryan (1997). "Old MacDonald Named a Compound: Branched Enynenynols" (PDF). Journal of Chemical Education 74 (7): 782. doi:10.1021/ed074p782. http://www.jce.divched.org/Journal/Issues/1997/Jul/PlusSub/V74N07/p782.pdf. Retrieved 2007-08-16. 
  5. ^ Prelog, V., Seiwerth,R. (1941). Berichte 74: 1644 and 1769. 
  6. ^ Not to be confused with the fictional material adamantium
  7. ^ a b c d e f g Nettleton DE Jr, Balitz DM, Doyle TW, Bradner WT, Johnson DL, O'Herron FA, Schreiber RH, Coon AB, Moseley JE, Myllymaki RW, J Nat Prod. 1980 Mar-Apr;43(2):242–258.
  8. ^ G. Märkl and H. Hauptmann (1983-06-14). "Untersuchungen zur Chemie der Arsole 1,1-dichlor-1-R-λ5-arsole-1-chlorarsole 2,2′,5,5′-tetraphenyldiarsolyl (Studies on the chemistry of arsoles)". J. Organomet. Chem. 248 (3): 269–285. doi:10.1016/S0022-328X(00)98709-6. 
  9. ^ Mikael P. Johansson and Jonas Jusélius (2005). "Arsole Aromaticity Revisited". Lett. Org. Chem. (3): 469–474. http://www.helsinki.fi/~mpjohans/science/abstracts/008-abstract.html. 
  10. ^ Zimmerman, Howard E.;; Robert M. Paufler. "Bicyclo [2.2.2]octa-2,5,7-triene (barrelene), a unique cyclic six electron pi system". Journal of the American Chemical Society 82 (6): 1514–1515. doi:10.1021/ja01491a071. 
  11. ^ Schleyer, Paul von Rague; Eiji Osawa, Michael G. B. Drew (1968). "Nonacyclo[11.7.1.12,18.03,16.04,13.05,10.06,14.07,11.015,20docosane, a bastard tetramantane"] (PDF). J. Am. Chem. Soc 90 (18): 5034–5036. doi:10.1021/ja01020a053. http://pubs.acs.org/cgi-bin/searchRedirect.cgi/jacsat/1968/90/i18/pdf/ja01020a053.pdf. Retrieved 2007-08-15. [dead link]
  12. ^ Kroto, H.W.; Heath, J.R.; O'Brien, S.C.; Curl, R.F.; Smalley, R.E. Nature, 1985, 318(6042), 162.
  13. ^ Haymet, A.D.J. J. Am. Chem. Soc. 1986, 108, 319.
  14. ^ Doering, W. von E.; Roth, W. R. (1963). "A Rapidly Reversible Degenerate Cope Rearrangement : Bicyclo[5.1.0octa-2,5-diene"]. Tetrahedron 19 (5): 715–737. doi:10.1016/S0040-4020(01)99207-5. http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6THR-42H7VSF-15&_user=10&_coverDate=12%2F31%2F1963&_alid=1417428637&_rdoc=2&_fmt=high&_orig=search&_cdi=5289&_sort=r&_docanchor=&view=c&_ct=2&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=3c55b6721e1cb8c14ac0982a08ac1365. 
  15. ^ Ault, Addison (2001). "The Bullvalene Story. The Conception of Bullvalene, a Molecule That Has No Permanent Structure". J. Chem. Educ. 78 (7): 924. doi:10.1021/ed078p924. http://www.jce.divched.org/Journal/Issues/2001/Jul/abs924.html. 
  16. ^ NORDENSTROM BE (1951). "Effect of cadaverine and lysine on the urinary excretion of piperidine in rabbits". Acta pharmacologica et toxicologica 7 (3): 287–296. doi:10.1111/j.1600-0773.1951.tb02870.x. PMID 14856760. 
  17. ^ D.O. Chester and J.A. Elix, Australian Journal of Chemistry 32 (1979) 2565-2569 doi:10.1071/CH9792565
  18. ^ Verbrugge, P. A. (1977). "Unusual organic compounds. XXIV. Compounds with the formula (CH)n. (d). Synthesis of cubane, (CH)8; homocubanes". Chemie en Techniek (Amsterdam) 32 (4): 120–123. 
  19. ^ R A Klein, G P Hazlewood, P Kemp, and R M Dawson, Biochem J. 1979 December 1; 183(3): 691–700.
  20. ^ Apitz-Castro R, Béguin S, Tablante A, Bartoli F, Holt JC, Hemker HC (1995). "Purification and partial characterization of draculin, the anticoagulant factor present in the saliva of vampire bats (Desmodus rotundus)". Thromb. Haemost. 73 (1): 94–100. PMID 7740503. 
  21. ^ "NIST Standard Reference Database 69, June 2005 Release: NIST Chemistry WebBook - Pentachloronitrobenzene". http://webbook.nist.gov/cgi/cbook.cgi?Name=fart*&Units=SI&cTG=on&cTC=on&cTP=on&cTR=on. Retrieved 2007-08-16. 
  22. ^ Tandem radical approach to linear condensed cyclopentanoids. Total synthesis of (.+-.)-hirsutene Dennis P. Curran and Donna M. Rakiewicz J. Am. Chem. Soc.; 1985; 107(5) pp 1448 - 1449; doi:10.1021/ja00291a077
  23. ^ Isolation, structure and synthesis of hirsutene, a precursor hydrocarbon of coriolin biosynthesis Shigeo Nozoe, Jun Furukawa, Ushio Sankawa and Shoji Shibata Tetrahedron Letters Volume 17, Issue 3 , January 1976, Pages 195-198 doi:10.1016/0040-4039(76)80013-5
  24. ^ Hirsutene upside down
  25. ^ Hirsutene upside down
  26. ^ (PDF) Parent Hydride Names and Substantive Nomenclature. IUPAC. March 2004. pp. 16. http://www.iupac.org/reports/provisional/abstract04/RB-prs310804/Chap6-3.04.pdf. 
  27. ^ Blaser, Hans-Ulrich; Brieden, Walter; Pugin, Benoit; Spindler, Felix; Studer, Martin; Togni, Antonio (2002). "Solvias Josiphos ligands: from discovery to technical applications". Topics in Catalysis 19 (1): 3–16. doi:10.1023/A:1013832630565. 
  28. ^ SM Kupchan, KL Stevens, EA Rohlfing, BR Sickles, AT Sneden, RW Miller, RF Bryan, J. Org. Chem., 43(4) (1978) 586
  29. ^ Theerasilp S, Kurihara Y (August 1988). "Complete purification and characterization of the taste-modifying protein, miraculin, from miracle fruit". J. Biol. Chem. 263 (23): 11536–11539. PMID 3403544. http://www.jbc.org/cgi/reprint/263/23/11536. 
  30. ^ Charles O, Coolsaet B (1972). "[Prevention of hemorrhage in prostatic surgery. Apropos of the study of the hemostatic activity in prostatectomy of a new molecule: beta-naphthoquinone monosemicarbazone (Naftazone)]" (in French). Annales d'urologie 6 (3): 209–212. PMID 4562066. 
  31. ^ "PEPPSI Catalysts". http://www.sigmaaldrich.com/chemistry/chemical-synthesis/technology-spotlights/peppsi.html. Retrieved 2009-04-01. 
  32. ^ Uri J, Csoban G, Viragh E., Acta Physiol Hung. 1951;2(2):223-8.
  33. ^ "Canadian Patents Database CA 1110562: Anthracycline antibiotic designated RUDOLPHOMYCIN". http://patents1.ic.gc.ca/details?patent_number=1110562. Retrieved 2007-08-16. 
  34. ^ Toma SH, Uemi M, Nikolaou S, Tomazela DM, Eberlin MN, Toma HE., Inorg Chem. 2004 May 31; 43(11):3521–3527
  35. ^ See, for example, N Okibe and DB Johnson, Biotechnology Letters, 2004 24(23), 2011–2016 doi:10.1023/A:1021118915720

References

  • Paul May, "Molecules with Silly or Unusual Names," Imperial College Press, July 2008, ISBN 978-1848162075.
  • Alex Nickon and Ernest F. Silversmith, "Organic Chemistry, the Name Game: Modern Coined Terms and Their Origins", Pergamon 1987. ISBN 0-08-034481-X.
  • W. V. Metanomski, "Unusual Names Assigned to chemical substances", Chem. Int., 1987, 9, 211-215.
  • J. Andraos, "Glossary of Coined Names & Terms Used in Science", York University, 2004.
  • E.C. Alyea, "Metal Complexes of Ditertiary Arsines. Chapter in Transition Metal Complexes of Phosphorus, Arsenic and Antimony Ligands", MacMillan, 1973. Chapter: "Some amusing names of arsine ligands: edas, vdias, dam, ffars etc"
  • Giles, P.M. (1999). "Revised Section F: Natural products and related compounds". Pure Appl. Chem. 71 (4): 587–643. doi:10.1351/pac199971040587. http://www.chem.qmul.ac.uk/iupac/sectionF/. Retrieved 2007-08-16. 

External links


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • Chemical nomenclature — A chemical nomenclature is a set of rules to generate systematic names for chemical compounds. The nomenclature used most frequently worldwide is the one created and developed by the International Union of Pure and Applied Chemistry (IUPAC). The… …   Wikipedia

  • List of fictional elements, materials, isotopes and atomic particles — This list contains chemical elements, materials, isotopes or (sub)atomic particle that exist primarily in works of fiction (usually fantasy or science fiction). No actual periodic elements end in ite , though many minerals have names with this… …   Wikipedia

  • List of Ig Nobel Prize winners — This is a list of Ig Nobel Prize winners from 1991 to the present day. A parody of the Nobel Prizes, the Ig Nobel Prizes are given each year in early October around the time the recipients of the genuine Nobel Prizes are announced for ten… …   Wikipedia

  • List of vegetable oils — Plant oils Olive oil Types Vegetable fats (list) Macerated (list) Uses …   Wikipedia

  • List of French words and phrases used by English speakers — Here are some examples of French words and phrases used by English speakers. English contains many words of French origin, such as art, collage, competition, force, machine, police, publicity, role, routine, table, and many other Anglicized… …   Wikipedia

  • English words with uncommon properties — For the purposes of this article, any word which has appeared in a recognised general English dictionary published in the 20th century or later is considered a candidate. For interest, some archaic words, non standard words and proper names are… …   Wikipedia

  • Glossary of terms associated with diabetes — This page lists and explains terms connected with diabetes. NOTOC A *Acanthosis nigricans A brown to black, poorly defined, velvety hyperpigmentation of the skin, usually present in the posterior and lateral folds of the neck, the axilla, groin,… …   Wikipedia

  • International Union of Pure and Applied Chemistry nomenclature — IUPAC nomenclature is a system of naming chemical compounds and of describing the science of chemistry in general. It is developed and kept up to date under the auspices of the International Union of Pure and Applied Chemistry (IUPAC).The rules… …   Wikipedia

  • Trivial name — In chemistry and zoology, a trivial name (also a common name or vernacular name ) is a non systematic name. That is, the name is not recognised according to the rules of any formal ( e.g. IUPAC) system of nomenclature. Many trivial names continue …   Wikipedia

  • Plant physiology — is a subdiscipline of botany concerned with the function, or physiology, of plants.Salisbury, Frank B. Cleon W. Ross, 1992. Plant physiology , 4th ed. (Belmont, California: Wadsworth Publishing). ISBN 0 534 15162 0] Closely related fields include …   Wikipedia