Rebaudioside A
{{Chembox
| Name =
| ImageFile = Rebaudioside A.svg
| ImageSize = 250px
| ImageAlt =
| IUPACName = β-D-Glucopyranosyl 13-{β-D-glucopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→3)]-β-D-glucopyranosyloxy}-5β,8α,9β,10α,13α-kaur-16-en-18-oate
| SystematicName = (2S,3R,4S,5S,6R)-3,4,5-Trihydroxy-6-(hydroxymethyl)oxan-2-yl (4R,4aS,6aR,9S,11aR,11bS)-9-{[(2S,3R,4S,5R,6R)-5-hydroxy-6-(hydroxymethyl)-3,4-bis{[(2S,3R,4S,5S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxy}oxan-2-yl]oxy}-4,11b-dimethyl-8-methylidenetetradecahydro-6a,9-methanocyclohepta[a]naphthalene-4-carboxylate
| OtherNames =
| Section1 = {{Chembox Identifiers
| CASNo = 58543-16-1
| PubChem = 124378
| ChEBI = 145012
| ChEMBL = CHEMBL430341
| ChemSpiderID = 5294031
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = B3FUD0528F
| SMILES = [C@]123[C@]([C@]4([C@@]([C@](CCC4)(C)C(O[C@@H]5O[C@@H]([C@@H](O)[C@@H]([C@H]5O)O)CO)=O)(CC1)[H])C)(CC[C@@](C2)(O[C@H]6[C@H](O[C@@H]7O[C@@H]([C@@H](O)[C@@H]([C@H]7O)O)CO)[C@H]([C@H](O)[C@H](O6)CO)O[C@@H]8O[C@@H]([C@@H](O)[C@@H]([C@H]8O)O)CO)C(C3)=C)[H]
}}
| Section2 = {{Chembox Properties
| Formula = C44H70O23 Rebaudioside A MATERIAL SAFETY DATA SHEET November 6, 2006
| MolarMass = 967.01 g/mol
| Appearance = white powder
| Density =
| MeltingPt =
| BoilingPt =
| Solubility =
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| Section3 = {{Chembox Hazards
| MainHazards =
| FlashPt =
| AutoignitionPt =
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| Section4 =
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| Section6 =
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Rebaudioside A (sometimes shortened to "Reb A") is a steviol glycoside from the leaves of Stevia rebaudiana that is 240 times sweeter than sugar.{{cite encyclopedia | last1 = Izawa | first1 = Kunisuke | last2 = Amino | first2 = Yusuke | last3 = Kohmura | first3 = Masanori | last4 = Ueda | first4 = Yoichi | last5 = Kuroda | first5 = Motonaka | editor-last1 = Liu | editor-first1 = Hung-Wen (Ben) | editor-last2 = Mander | editor-first2 = Lew | encyclopedia = Comprehensive Natural Products II | title = 4.16 - Human–Environment Interactions – Taste | language = English | year = 2010 | publisher = Elsevier | volume = 4 | pages = 631–671 | isbn = 978-0-08-045382-8 | doi = 10.1016/B978-008045382-8.00108-8 | quote = "Among the glycosides, stevioside is the most abundant followed by rebaudioside A. Stevioside is 140 times sweeter than sucrose, while rebaudioside is 240 times sweeter." | ref = CNPII-4.16}} Rebaudioside A is the sweetest and most stable steviol glycoside, and is less bitter than stevioside.{{cite journal | vauthors=Goyal SK, Samsher, Goyal RK | title=Stevia (Stevia rebaudiana) a bio-sweetener: a review | journal=International Journal of Food Sciences and Nutrition | volume=61 | issue=1 | pages=1–10 | year=2010 | doi = 10.3109/09637480903193049 | pmid=19961353| s2cid=24564964 }} Stevia leaves contain 9.1% stevioside and 3.8% rebaudioside A.
The glycoside contains only glucose (to the exclusion of other commonly found monosaccharides) as its monosaccharide moieties. It contains four glucose molecules in total with the central glucose of the triplet connected to the main steviol structure at its hydroxyl group, and the remaining glucose at its carboxyl group forming an ester bond.