Amber, oil

The solvent is then evaporated, and the unconverted sterol is recovered by precipitation from an appropriate solvent, eg, alcohol. The recovered sterol is reused in subsequent irradiations. The solvent is then evaporated to yield vitamin D resin. The resin is a pale yeUow-to-amber oil that flows freely when hot and becomes a brittie glass when cold the activity of commercial resin is 20 30 x 10 lU/g. The resin is formulated without further purification for use in animal feeds. Vitamin D can be crystallized to give the USP product from a mixture of hydrocarbon solvent and ahphatic nitrile, eg, benzene and acetonitrile, or from methyl formate (100,101). Chemical complexation has also been used for purification. 

Amber-fett, -harz, n. ambrain. -kraut, n. cat thyme (Teucrium marum). -81, n. oil of amber, amber oil. -stoff, m. ambrain. Amboss, m. anvil (Anat.) incus. 

A solution of 5 (from 44.2 g of the dimer) in 750 mL of THF is added under nitrogen by forced siphon through a stainless steel cannula to a stirred, cooled ( —78 X) solution of 50.9 g (0.54 mol) of chloromethyl menthyl ether (6) in 150 mL of THF. After addition, the solution is allowed to warm to 25 X, stirred for an additional 2 h. then the solvent is removed under reduced pressure. 800 mL of pentane are added and the slurry is filtered through a cake of anhyd MgS04. Solvent removal and chromatography of the residue [alumina, hexane, then (C2H5)20/hexane 1 10] affords menthyloxymethyl complex 7 as an amber oil yield 78.5 g (91%). 

The checkers purchased N-(tert-butoxycarbonyl)-L-scrinc methyl ester from Aldrich Chemical Company, Inc. The submitters prepared this compound, a thick amber oil, according to the procedure described in Dondoni, A. Perrone, D. Org. Synth. Coll. Vol. X, 2004, 320. 

A simple epoxide related to ionone has been isolated from amber oil by Ruzicka and Seidel, and the structure (Xll) tentatively assigned to it.1413 Vitamin A epoxide (XIII) is believed to coexist with vitamh... 

SYNTHESIS To a solution of 14.0 g 4-ethoxy-3-methoxyphenol (see the recipe for MME for the preparation of this starting material) in an equal volume of EtOH, there was added a solution of 5.3 g KOH in 100 mL hot MeOH. This was followed with 9.1 g ethyl bromide, and the mixture was held at reflux for 2 h. The first deposition of KBr was apparent in 5 min, and there was rather severe bumping by the end of the reaction. The mixture was diluted with 3 volumes H20 and 1 volume 5% NaOH, and extracted with 2x200 mL Et20. The extracts were pooled, and the solvent removed under vacuum, yielding 14.3 g of a pale amber oil that set to crystals of 2,5-diethoxyanisole with a mp of 44-45 °C. The compound had been reported in the literature from the action of diethyl sulfate on methoxyhydroquinone. 

SYNTHESIS To a solution of 43.2 g KOH pellets in 250 boiling EtOH there was added 96 g 4-methoxyphenol followed by the slow addition of 131.2 g allyl bromide, and the mixture was held under refluxing conditions for 16 h. After cooling, the reaction was added to 1.6 L H20, and made strongly basic with 25% NaOH. This was extracted with 3x100 mL CH,C1, the extracts pooled, washed once with dilute NaOH and then once with dilute HC1. Removal of the solvent under vacuum gave 93.8 g of 4-allyloxyanisole as a pale amber oil, which was used in the following reaction without further purification,... 

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