In organic chemistry, an acetonide is the functional group composed of the cyclic ketal of a

diol A diol is a chemical compound containing two hydroxyl groups ( groups). An aliphatic diol is also called a glycol. This pairing of functional groups is pervasive, and many subcategories have been identified. The most common industrial diol is e ...

with acetone. The more systematic name for this structure is an isopropylidene ketal. Acetonide is a common

protecting group A protecting group or protective group is introduced into a molecule by chemical modification of a functional group to obtain chemoselectivity in a subsequent chemical reaction. It plays an important role in multistep organic synthesis. In many ...

for 1,2- and 1,3-

s. The protecting group can be removed by hydrolysis of the ketal using dilute aqueous

acid In computer science, ACID ( atomicity, consistency, isolation, durability) is a set of properties of database transactions intended to guarantee data validity despite errors, power failures, and other mishaps. In the context of databases, a sequ ...

Example

The acetonides of small di- and triols, as well as many

sugar Sugar is the generic name for sweet-tasting, soluble carbohydrates, many of which are used in food. Simple sugars, also called monosaccharides, include glucose, fructose, and galactose. Compound sugars, also called disaccharides or double ...

s and sugar alcohols, are common. The hexaol mannitol reacts with 2,2-dimethoxypropane to give the bis-acetonide, which oxidizes to give the acetonide of glyceraldehyde: :(CHOHCHOHCH₂OH)₂ + 2 (MeO)₂CMe₂ → (CHOHCHCH₂O₂CMe₂)₂ + 4 MeOH :(CHOHCHOCH₂OCMe₂)₂ + → 2 OCHCHCH₂O₂CMe₂ + H₂O An example of its use as a protecting group in a complex organic synthesis is the Nicolaou Taxol total synthesis. It is a common protecting group for sugars and sugar alcohols, a simple example being

solketal Solketal is a protected form of glycerol with an isopropylidene acetal group joining two neighboring hydroxyl groups. Solketal contains a chiral center on the center carbon of the glycerol backbone, and so can be purchased as either the racemate ...

. The acetonides of

corticosteroid Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex of vertebrates, as well as the synthetic analogues of these hormones. Two main classes of corticosteroids, glucocorticoids and mineralocorticoids, are involv ...

are used in dermatology, because their increased lipophilicity leads to better penetration into the skin. *

Fluclorolone acetonide Fluclorolone acetonide (INN, or flucloronide, USAN 280px, "Samguk Sagi" Book 04. Silla's Records. In 512, Usan-guk（于山國）was Ulleungdo（鬱陵島） Usan-guk, or the State of Usan, occupied Ulleung-do and the adjacent islands dur ...

* Fluocinolone acetonide * Triamcinolone acetonide

References

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Example

See also

References