Sucrose octaacetate: Difference between revisions

| Watchedfields = changed

| verifiedrevid = 441320670

| ImageFile =Sucrose octaacetate.png

| ImageSize =

| IUPACName = 1,3,4,5-Tetra-''O''-acetyl-β-<small>D</small>-fructofuranosyl α-<small>D</small>-glucopyranoside 2,3,4,6-tetraacetate

| SystematicName = (2''R'',3''R'',4''S'',5''R'',6''R'')-6-<nowiki>{</nowiki>[(2''S'',3''S'',4''R'',5''R'')-2,3,4,5-Tetrakis(acetyloxy)oxolan-2-yl]oxy<nowiki>}</nowiki>oxane-2,3,4,5-tetrayl tetraacetate

| OtherNames = Acetic acid [(2''S'',3''S'',4''R'',5''R'')-4-acetoxy-2,5-bis(acetoxymethyl)-2-{[(2''R'',3''R'',4''S'',5''R'',6''R'')-3,4,5-triacetoxy-6-

(acetoxymethyl)-2-tetrahydropyranyl]oxy}-3-tetrahydrofuranyl] ester

|Section1={{Chembox Identifiers

| CASNo_Ref = {{cascite|correct|CAS}}

| CASNo =126-14-7

| UNII_Ref = {{fdacite|correct|FDA}}

| UNII = 07V591057T

| PubChem =31340

| SMILES = CC(=O)OC[C@@H]1[C@H]([C@@H]([C@H]([C@H](O1)O[C@]2([C@H]([C@@H]([C@H](O2)COC(=O)C)OC(=O)C)OC(=O)C)COC(=O)C)OC(=O)C)OC(=O)C)OC(=O)C

|Section2={{Chembox Properties

| Formula =C₂₈H₃₈O₁₉

| MolarMass =678.59 g/mol

| Appearance = colorless needles

| Odor = odourless

| Density =1.27 g/cm³ at 16 °C

| MeltingPtC = 86.5

| BoilingPtC = 250

| BoilingPt_notes = at 1 [[mmHg]]

| Solubility =slightly soluble in water

| SolubleOther =soluble in [[ethanol]], [[diethyl ether]], [[acetone]], [[benzene]], [[chloroform]],<ref name=lide1998/> [[toluene]]<ref name=cox1933/>

|Section3={{Chembox Hazards

| MainHazards =

| FlashPt =

| AutoignitionPt =

}}

'''Sucrose octaacetate''' is a [[chemical compound]] with formula {{chem|C|28|H|38|O|19}}or {{chem|(C|2|H|3|O|2|)|8|(C|12|H|14|O|3|)}}, an eight-fold [[ester]] of [[sucrose]] and [[acetic acid]]. Its [[molecule]] can be described as that of sucrose {{chem|C|12|H|22|O|11}} with its eight [[hydroxyl]] groups {{chem|HO}}– replaced by [[acetate]] groups {{chem|H|3|C–C|O|2}}–. It is a [[crystal]]line solid, colorless and odorless but intensely bitter.<ref name=cox1933/>

Sucrose octaacetate is used as an [[inert ingredient]] in [[pesticide]]s and [[herbicide]]s, as a [[bitterant|bitter additive]].

==History==

The preparation of sucrose octaacetate was first described in 1865 by [[Paul Schutzenberger|P. Schutzenberger]],<ref name=schut1865/> but its purification and characterization were first published by [[A. Herzfeld]] in 1887.<ref name=herz1887/><ref name=cox1933/>

==Preparation==

The compound can be prepared by the [[exothermic reaction]] of sucrose with [[acetic anhydride]] at about 145 °C, with [[sodium acetate]] as [[catalyst]].<ref name=cox1933/> The product can be purified by dissolution in ethanol and recrystallization.<ref name=stag2019/>

==Properties==

===Structure===

The structure of the crystallized form was determined by [[J. D. Oliver]] and [[L. C. Strickland]] in 1984, using [[X-ray diffraction]]. The crystal system is [[orthorhombic]], symmetry group P2₁2₁2₁, with parameters ''a'' = 1.835 [[nanometre|nm]], ''b''= 2.144 nm, ''c''= 0.835 nm, ''Z''=4, ''V''=3.285 nm³, ''D''_''x'' = 1.372 [[gram|g]]/[[millilitre|mL]]. The [[pyranose]] and [[furanose]] rings are in "chair" (⁴C₁) and "twist" (⁴T₁) [[carbohydrate conformation|conformations]], respectively, unlike their conformations in saccharose.<ref name=oliv1984/>

===Physico-chemical===

Sucrose octaacetate is only slightly soluble in water (sources give 0.25 to 1.4 [[gram|g]]/L at room temperature) but is soluble in many common organic solvents such as [[toluene]] and [[ethanol]], from which it can be crystallized by evaporation.<ref name=cox1933/> It is also soluble in [[supercritical carbon dioxide]].<ref name=anto2018/> It is a neutral molecule with no ionizable [[hydrogen]] atoms.<ref name=stag2019/>

The compound melts into a viscous liquid (29.54 [[Poise (unit)|poise]]s at 100.2 °C), that becomes a clear [[glass]]y solid on cooling.<ref name=cox1933/>

The [[density]] of the glassy form is 1.28 [[kilogram|kg]];[[litre|L]] (at 20 °C), its [[index of refraction]] ''n''_D²⁰ is 1.4660,its [[dielectric constant]] is 4.5 (at 1 [[kilohertz|kHz]]), and its [[resistivity]] is 1.5 × 10¹⁴ [[ohm|Ω]] [[centimetre|cm]]. It is [[optical activity|optically active]] with [α]_D²⁴ = +59.79°.<ref name=cox1933/>

The compound slowly [[hydrolysis|hydrolyzes]] in water: 0.25% of the acetate ester bonds were broken by boiling in water for 1 hour, and 0.20% after standing in water at 40&nbsp;°C for 5 days.

Sucrose octaacetate decomposes at about 285 °C, but can be distilled at reduced pressure at 260&nbsp;°C.<ref name=cox1933/>

===Organoleptic===

The compound is odorless but intensely [[bitterness (taste)|bitter]], being detectable at a concentration of 1–2 [[part per million|ppm]].<ref name=cox1933/> Adding 0.6 [[gram|g]] of the compound to 1 [[kilogram|kg]] of sugar renders it too bitter to eat.<ref name=stag2019/>

===Melting point and possible polymorphism===

There has been significant discrepancy in the reported melting point of the crystalline compound. Five reports spanning 1880 to 1928 gave it as 69–70 °C. In 1930, a crystal form was reported to melt at 75 °C. In 1936, another report described a different crystal form and a melting point of 83 °C. In 1940, the same authors found 89 °C. All reports since then have given melting points in 83–89 °C range.<ref name=stag2019/>

It was conjectured that the differences could be due to [[polymorphism (materials science)|polymorphism]]; namely, that the compound could crystallize in two or more different crystal structures, with different melting points. However, modern studies, including X-ray diffraction, failed to find any evidence of polymorphism.<ref name=stag2019/>

==Reactions==

Sucrose octaacetate can be converted to other eightfold fatty acid esters of sucrose by reacting it with the appropriate [[triglyceride]] with [[sodium methoxide]] as catalyst. This way one can obtain sucrose [[caprylic acid|octacaprylate]] (C₈ chain), [[capric acid|octacaprate]] (C₁₀, [[melting point|m.p]] −24 °C) [[lauric acid|octalaurate]] (C₁₂, 10 °C), [[myristic acid|octamyristate]] (C₁₄, 34 °C), [[palmitic acid|octapalmitate]], (C₁₆, 50.5 °C), [[stearic acid|octastearate]] (C₁₈, 61 °C), [[oleic acid|octaoleate]] (C₁₈ ''cis''-9), [[elaidic acid|octaelaidate]] (C₁₈ ''trans''-9, 7.4 °C), and [[linoleic acid|octalinoleate]] (C₁₈ ''cis''-9,12).<ref name=jand1978/>

==Applications==

===Bitterant===

Sucrose octaacetate has been used to determine tasters from non-tasters in mice,<ref name=hard1992/> in clinical drug studies and [[sweetener]] evaluations,<ref name=stag2019/> and in taste physiology research.<ref name=stag2019/>

The product has also been used as a [[bitterant]] and [[aversive agent]].<ref name=epa310.536/> Until 1993, the compound was the active ingredient of over-the-counter preparations to discourage thumb sucking and nail biting. It has also been used in sprays and lotions to prevent dog licking, and as an additive to deter ingestion of pesticides and other toxic products. <ref name=stag2019/>

===Flavoring agent===

Sucrose octaacetate is used as a flavoring agent in foods and beverages, such as in [[bitter (beverage)|bitters]] and [[ginger ale]].<ref name=stag2019/>

===Plasticizer===

Sucrose octaacetate has been used as an adhesive and as a [[plasticizer]] in lacquers and plastics.<ref name=stag2019/> While the crystalline character of the pure compound is an obstacle for this latter application, mixed esters where some acetate groups are replaced by [[propionate]] or [[isobutyric acid|isobutyrate]] can be used.<ref name=touey1960/>

==Safety==

Due to its low toxicity, sucrose octaacetate was authorized by the US Environment Protection Agency for use as an inert ingredient in pesticides,<ref name=jarv2005/> as [[food additive]],<ref name=epa172.515/><ref name=epa175.105/> and as a nail-biting and thumb-sucking deterrent in over-the-counter drug products.<ref name=epa310.536/>

==See also==

* [[Glucose pentaacetate]]

* [[Sucrose octapropionate]]

* [[Sucrose octabutyrate]]

<references>

<ref name=schut1865>P. Schutzenberger (1865): "Action de l'acide acétique anhydre sur la cellulose, les sucres, la mannite et ses congénères". ''Comptes rendus des séances de l'académie des sciences'', volume 61, page 485.</ref>

<ref name=herz1887>A. Herzfeld (1887): ''Zeitschrift des Vereins der deutschen Zucker-Industrie'', volume 37, page 422.</ref>

<ref name=cox1933>Gerald J. Cox, John H. Ferguson, and Mary L. Dodds (1933): "III. Technology of Sucrose Octaäcetate and Homologous Esters". ''Industrial & Engineering Chemistry'', volume 25, issue 9, pages 968–970. {{doi|10.1021/ie50285a006}}</ref>

<ref name=oliv1984>J. D. Oliver and L. C. Strickland (1984): "Structure of sucrose octaacetate, C₂₈H₃₈O₁₉, at 173 K". ''Acta Crystallographica Section C'', volume 40, issue 5, pages 820-824. {{doi|10.1107/S0108270184005850}}</ref>

<ref name=lide1998>David R. Lide (1998): ''Handbook of Chemistry and Physics''. CRC Press. {{isbn|0-8493-0594-2}}</ref>

<ref name=jarv2005>Christina M. Jarvis (2005): "[https://www.epa.gov/sites/production/files/2015-04/documents/sucrose.pdf Reassessment of the Exemption from the Requirement of a Tolerance for Sucrose Octaacetate (CAS Reg. No. 126-14-7)]". Mamorandum dated 2005-12-21, CFR 180.910.</ref>

<ref name=hard1992>David B. Harder, Christopher G. Capeless, John C. Maggio, John D. Boughter, Jr, Kimberley S. Gannon, Glayde Whitney, and Edwin A. Azen (1992): "Intermediate sucrose octa-acetate sensitivity suggests a third allele at mouse bitter taste locus Soa and Soa-Rua identity". ''Chemical Senses'', volume 17, issue 4, pages 391–401,. {{doi|10.1093/chemse/17.4.391}}</ref>

<ref name=touey1960>George P. Touey and Herman E. Davis (1960): "[https://patentimages.storage.googleapis.com/f2/d8/91/e650c9df1f4866/US2931802.pdf Mixed esters of glucose and sucrose]". US Patent 2931802, assigned to Eastman Kodak Co.</ref>

<ref name=jand1978>Ronald J. Jandacek and Marjorie R. Webb (1978): "Physical properties of pure sucrose octaesters". ''Chemistry and Physics of Lipids'', volume 22, issue 2, pages 163-176. {{doi|10.1016/0009-3084(78)90042-7}}</ref>

<ref name=epa172.515>US Environment Protection Agency, 21 CFR 172.515</ref>

<ref name=epa175.105>US Environment Protection Agency, 21 CFR 175.105</ref>

<ref name=epa310.536>US Environment Protection Agency, 21 CFR 310.536</ref>

<ref name=anto2018>Anu Antony, Jyothi P. Ramachandran, Resmi M. Ramakrishnan, and Poovathinthodiyil Raveendran (2018): "Sizing of paper with sucrose octaacetate using liquid and supercritical carbon dioxide as a green alternative medium". ''Journal of CO2 Utilization'', volume 28, pages 306-312. {{doi|10.1016/j.jcou.2018.10.011}}</ref>

<ref name=stag2019>William Craig Stagner, Shalini Gaddam, Rudrangi Parmar, and Ajay Kumar Ghanta (2019): "Sucrose octaacetate". Chapter 5 of ''Profiles of Drug Substances, Excipients and Related Methodology'', volume 44, pages 267-291 {{doi|10.1016/bs.podrm.2019.02.002}}</ref>

</references>