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Names | |
---|---|
Preferred IUPAC name
Cyclopentane-1,2,3,4,5-pentol | |
Other names
1,2,3,4,5-Cyclopentanepentol
1,2,3,4,5-Pentahydroxycyclopentane | |
Identifiers | |
| |
3D model (
JSmol)
|
|
ChemSpider | |
PubChem
CID
|
|
CompTox Dashboard (
EPA)
|
|
| |
Properties | |
C5H10O5 | |
Molar mass | 150.130 g·mol−1 |
Except where otherwise noted, data are given for materials in their
standard state (at 25 °C [77 °F], 100 kPa).
|
1,2,3,4,5-Cyclopentanepentol, also named cyclopentane-1,2,3,4,5-pentol or 1,2,3,4,5-pentahydroxycyclopentane is a
chemical compound with formula C
5H
10O
5 or (–CHOH–)
5, whose
molecule consists of a ring of five
carbon atoms (a
cyclopentane skeleton), each connected to one
hydrogen and one
hydroxyl
group.
[1] The unqualified term "cyclopentanepentol" usually refers to this compound. There are four distinct
stereoisomers with this same structure.
[2]
The compound is a five-fold alcohol of cyclopentane, and technically a cyclic sugar alcohol (a cyclitol). However it is very rarely found in nature, and therefore it has received much less attention than the ubiquitous six-carbon version, inositol. [3]
There are four distinct stereoisomers of cyclopentane-1,2,3,4,5-pentol, distinguished by the position of the hydroxyls relative to the mean plane of the ring. All have a plane of symmetry, and therefore are not chiral. One naming convention for the isomers labels each carbon number 1-5 with "α" for the side of the ring plane with most hydroxyls (three or more), and "β" for the other side. Another convention lists the hydroxyls on the majority side and then those on the minority side, with the two groups separated by a slash (and a "0" is written when the second list would be empty). [4]
The four possible isomers are: [2]
The last three isomers interconvert by heating them at about 104 °C with 95% acetic acid in the presence of a strong acid. The conversion between 1,2,3,4/5 and 1,2,3/4,5 is faster and entails the hydrogen and hydroxyl switching places on either of the two carbon atoms located between an "α" and a "β" position. The formation of 1,2,4/3,5 is much slower and equilibrium is reached only after many days. The relative stabilities are 1,2,4/3,5 > 1,2,3/4,5 > 1,2,3,4/5, with equilibrium ratios 72 : 17.5 : 10.5. [3]
The isomers can be identified qualitatively by their mobility in paper ionophoresis in a solution of calcium acetate and acetic acid, and revealed with a manganese sulfate/ potassium permanganate reagent. The mobilities of the isomers, relative to that of cis-inositol, are 0.95 (12345/0), 0.44 (1234/5), 0.18 (123/45), and 0.04 (124/35). The variation is attributed to the formation of chelates with the calcium cations, with varying strengths depending on the number of hydroxyl pairs that can bind to the cation. [9] Similar results can be obtained with lanthanum cations and thin-layer chromatography. [10]
Mass spectrometry of the compound generates mainly the ion HO–CH=CH=CH=O+H (mass-charge ratio 73) and a neutral radical C
2H
5O•.
[11]
Many esters are known, such as penta benzoyls [2] and penta acetyls. [3]
Trteatment of the derivative 3,4,5-tri-O-acetyl-1,2-O-ethylidene-(1,2,4/3,5)-cyclopentanepentol with
triphenylcarbenium
tetrafluoroborate [(C
6H
5)
3C]+
[BF
4−
to yield the cation 3,4,5-tri-O-acetyl-(1,2,4/3,5)-cyclopentanepentol-1,2-O-acetoxonium, which exhibits a peculiar 10-stage cyclic rearrangement.
[12]
Cyclopentanepentols form dihydrogen phosphate esters analogous to inositol's phytic acid esters. [13]
The related compound 1,2,3,4,5-pentakis(hydroxymethyl)-cyclopentane (a colourless viscous oil, soluble in tert-butanol and DMSO) was synthesized in 1985 by L. M. Tolbert and others. It was hoped that dehydrative dimerization of this product would yield dodecahedrane. [14]
Organic compounds similar to (and possibly mimicking) glycoglycerolipids, [15] with a 1,2,4/3,5-cyclopentanepentol group connected to the glycerol core in place of the sugar group, have been found in several genera of marine sponges with widely separate ranges. [16] [17] [18] [19] [20] [21]
Calditol is a substance found in the archaeobacteria of the order Sulfolobales. It is an ether that can be viewed as the condensation of glycerol and 3α-hydroxymethyl-1α,2α,3β,4α,5β-hydroxy cyclopentane, forming an ether bridge –O– between the 1-carbon of the former and the 4-carbon of the latter. [22] Its seems to protects the cells in acidic environments. [23]
Trace amounts of cyclopentanepentol were identified in some plants, such as the red flower calyces of Hibiscus sabdariffa (roselle); [24] the plant Maclura pomifera (Osage orange); [25] and the cyanobacterium Oscillatoria willei [26] as well as in the products of its hydropyrolysis. [27]
The 1,2,4/3,5 isomer was briefly described in 1963 by H. Z. Sable and others. [7] In 1968, Th. Posternak reported observation of 1,2,3,4/5 and 1,2,3/4,5, without the synthesis method. [28] Better synthesis methods for these three were published by S. J. Angyal and B. M. Luttrell in 1970. [3] Alternative methods for 1,2,3,4/5 and 1,2,3/4,5 were published in the same year by G. Wolczunowicz and others. [6] The remaining all-cis isomer (1,2,3,4,5/0) was synthesized in 1971 by F. G. Cocu and Posternak. [5]
![]() | |
Names | |
---|---|
Preferred IUPAC name
Cyclopentane-1,2,3,4,5-pentol | |
Other names
1,2,3,4,5-Cyclopentanepentol
1,2,3,4,5-Pentahydroxycyclopentane | |
Identifiers | |
| |
3D model (
JSmol)
|
|
ChemSpider | |
PubChem
CID
|
|
CompTox Dashboard (
EPA)
|
|
| |
Properties | |
C5H10O5 | |
Molar mass | 150.130 g·mol−1 |
Except where otherwise noted, data are given for materials in their
standard state (at 25 °C [77 °F], 100 kPa).
|
1,2,3,4,5-Cyclopentanepentol, also named cyclopentane-1,2,3,4,5-pentol or 1,2,3,4,5-pentahydroxycyclopentane is a
chemical compound with formula C
5H
10O
5 or (–CHOH–)
5, whose
molecule consists of a ring of five
carbon atoms (a
cyclopentane skeleton), each connected to one
hydrogen and one
hydroxyl
group.
[1] The unqualified term "cyclopentanepentol" usually refers to this compound. There are four distinct
stereoisomers with this same structure.
[2]
The compound is a five-fold alcohol of cyclopentane, and technically a cyclic sugar alcohol (a cyclitol). However it is very rarely found in nature, and therefore it has received much less attention than the ubiquitous six-carbon version, inositol. [3]
There are four distinct stereoisomers of cyclopentane-1,2,3,4,5-pentol, distinguished by the position of the hydroxyls relative to the mean plane of the ring. All have a plane of symmetry, and therefore are not chiral. One naming convention for the isomers labels each carbon number 1-5 with "α" for the side of the ring plane with most hydroxyls (three or more), and "β" for the other side. Another convention lists the hydroxyls on the majority side and then those on the minority side, with the two groups separated by a slash (and a "0" is written when the second list would be empty). [4]
The four possible isomers are: [2]
The last three isomers interconvert by heating them at about 104 °C with 95% acetic acid in the presence of a strong acid. The conversion between 1,2,3,4/5 and 1,2,3/4,5 is faster and entails the hydrogen and hydroxyl switching places on either of the two carbon atoms located between an "α" and a "β" position. The formation of 1,2,4/3,5 is much slower and equilibrium is reached only after many days. The relative stabilities are 1,2,4/3,5 > 1,2,3/4,5 > 1,2,3,4/5, with equilibrium ratios 72 : 17.5 : 10.5. [3]
The isomers can be identified qualitatively by their mobility in paper ionophoresis in a solution of calcium acetate and acetic acid, and revealed with a manganese sulfate/ potassium permanganate reagent. The mobilities of the isomers, relative to that of cis-inositol, are 0.95 (12345/0), 0.44 (1234/5), 0.18 (123/45), and 0.04 (124/35). The variation is attributed to the formation of chelates with the calcium cations, with varying strengths depending on the number of hydroxyl pairs that can bind to the cation. [9] Similar results can be obtained with lanthanum cations and thin-layer chromatography. [10]
Mass spectrometry of the compound generates mainly the ion HO–CH=CH=CH=O+H (mass-charge ratio 73) and a neutral radical C
2H
5O•.
[11]
Many esters are known, such as penta benzoyls [2] and penta acetyls. [3]
Trteatment of the derivative 3,4,5-tri-O-acetyl-1,2-O-ethylidene-(1,2,4/3,5)-cyclopentanepentol with
triphenylcarbenium
tetrafluoroborate [(C
6H
5)
3C]+
[BF
4−
to yield the cation 3,4,5-tri-O-acetyl-(1,2,4/3,5)-cyclopentanepentol-1,2-O-acetoxonium, which exhibits a peculiar 10-stage cyclic rearrangement.
[12]
Cyclopentanepentols form dihydrogen phosphate esters analogous to inositol's phytic acid esters. [13]
The related compound 1,2,3,4,5-pentakis(hydroxymethyl)-cyclopentane (a colourless viscous oil, soluble in tert-butanol and DMSO) was synthesized in 1985 by L. M. Tolbert and others. It was hoped that dehydrative dimerization of this product would yield dodecahedrane. [14]
Organic compounds similar to (and possibly mimicking) glycoglycerolipids, [15] with a 1,2,4/3,5-cyclopentanepentol group connected to the glycerol core in place of the sugar group, have been found in several genera of marine sponges with widely separate ranges. [16] [17] [18] [19] [20] [21]
Calditol is a substance found in the archaeobacteria of the order Sulfolobales. It is an ether that can be viewed as the condensation of glycerol and 3α-hydroxymethyl-1α,2α,3β,4α,5β-hydroxy cyclopentane, forming an ether bridge –O– between the 1-carbon of the former and the 4-carbon of the latter. [22] Its seems to protects the cells in acidic environments. [23]
Trace amounts of cyclopentanepentol were identified in some plants, such as the red flower calyces of Hibiscus sabdariffa (roselle); [24] the plant Maclura pomifera (Osage orange); [25] and the cyanobacterium Oscillatoria willei [26] as well as in the products of its hydropyrolysis. [27]
The 1,2,4/3,5 isomer was briefly described in 1963 by H. Z. Sable and others. [7] In 1968, Th. Posternak reported observation of 1,2,3,4/5 and 1,2,3/4,5, without the synthesis method. [28] Better synthesis methods for these three were published by S. J. Angyal and B. M. Luttrell in 1970. [3] Alternative methods for 1,2,3,4/5 and 1,2,3/4,5 were published in the same year by G. Wolczunowicz and others. [6] The remaining all-cis isomer (1,2,3,4,5/0) was synthesized in 1971 by F. G. Cocu and Posternak. [5]