Myrac

Another synthesis of Lyral (51) consists of the reaction of myrcene with acrolein to give the myrac aldehyde [37677-14-8] (52). The aldehyde group, which is sensitive to acid hydration conditions with strong acids, has to be protected by formation of the morpholine enamine. The enamine is then hydrolyzed on workup after the acid-catalyzed hydration to produce Lyral (93—95). 

Myocardial infarction, 3 710-711 and blood coagulation, 4 81 Myocardial pacemaker cells, 5 81 Myocardium, 5 79—80 Myoglobin, properties of standard, 3 836t Myosin, role in heart excitation and contraction coupling, 5 81 Myrac aldehyde, 2 278 24 485 Myrascone, 24 571... 

Brand Name(s) Arestin, Dynacin, Minocin, Myrac, Vectrin Cfiemical Class Tetracycline derivative... 

Trade Names. Empetal (Quest), Myrac aldehyde (IFF), Myraldene (Giv.-Roure), Vertomugal (H R), Myrcenal (DRT). 

For example, the addition of acrolein to myrcene gives a product known by trade names such as Myrac Aldehyde or Empetal . The product is a mixture of isomers because the dienophile can line up in two orientations relative to the diene. For simplicity, only the major isomer, in which the two substituents on the cyclohexane ring are 1,4 relative to each other, is shown. Hydration of the acyclic double bond of Empetal gives a hydroxy-aldehyde, known as Hydroxy empetal or Lyral . Lyral possesses a fine odour reminiscent of the delicate odour of the flowers of lily of the valley and is widely used in perfumery. 

Addition of myrcene to acrolein gives the aldehyde (61), which is known under trade names such as Myrac Aldehyde, Empetal, Acropal, and Vernaldehyde [37677-14-8] and has a natural, green, and aldehydic odor. 

The most obvious synthesis of Lyral is to hydrate the double bond of Myrac Aldehyde (61) under acidic conditions. However, the aldehyde group is sensitive to acid and undergoes an intramolecular Prins reaction if this is attempted. It is therefore necessary to protect the aldehyde function prior to hydration, and this can be done by formation of an enamine or oxazolidine that can be removed by hydrolysis when hydration is complete [84, 85]. 

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