Commercial xanthhydrol may be used, but the pure white product, m.p. 120-121°, obtained by the reduction of xanthone with sodium amalgam (Section VII,16) gives better results.  [c.405]

The best results are obtained with freshly prepared xanthhydrol (reduction of xanthone with sodium amalgam. Section VII,16). Dissolve 0 -25 g. of xanthhydrol and 0 -25g. of the primary sulphonamide in 10 ml. of glacial acetic acid. Shake for 2-3 minutes at the laboratory temperature and allow to stand for 60-90 minutes. Filter oflf the derivative, recrystallise it from dioxan-water (3 1), and dry at room temperature under water pump suction for 30 minutes.  [c.558]

The characterisation of a primary aromatic amide is based upon its own m.p. and the identification of the acid (see Section IV,175) produced on hydrolysis. A crystalline derivative may be prepared directly with xanthhydrol (for experimental details, see Section 111,110, 1).  [c.799]

Phenyl salicylate upon heating alone yields xanthone the latter is reduced by sodium amalgam to xanthhydrol  [c.964]

Xanthone. Secure a 500 ml. Pyrex distilling flask with a side arm 20-25 cm. long and at least 10 mm. in diameter. Place 250 g. of phenyl sahcylate in the flask and fit it with two thermometers, one extending just below the side arm and the other to the bottom of the flask. Use a conical flask as a receiver. Heat the flask on an asbestos-centred wire gauze. When the temperature of the liquid reaches 275-285°, phenol commences to distil. Regulate the heating so that the temperature on the upper thermometer never exceeds 175°, but preferably remains below 170° phenol distils at the rate of 5-10 drops per minute. After 6-7 hours, the temperature of the liquid is 350-355° and phenol practically ceases to distil the weight of distillate at this point is about 110 g. Change the receiver, raise the lower thermometer from the hquidand distil the contents of the flask s rapidly as possible with a free flame until the tarry residue begins to foam. Pour the distillate (ca. 85 g.) whilst still hot into a cold evaporating dish, allow to cool, grind it in a mortar with 50 ml. of 5 per cent, sodium hydroxide solution, then warm it on a water bath for 10-15 minutes with 200 ml. of this alkah solution. When cold, filter oflF the xanthone, wash it until free from alkah, and dry at 100°. Remove a smaU amount of low-melting impurity by boiling for 15 minutes with 125 ml. of methyl alcohol, filter when cold, and wash with a httle methanol. The yield of xanthone, m.p. 171-172°, is 70 g. this is sufficiently pure for the preparation of xanthhydrol. If it is required pure, recrystallise from rectified spirit (20 ml. per 1 g. of xanthone) the m.p. is thereby raised to 173-174°.  [c.964]

Xanthhydrol. Prepare an amalgam from 9 0 g. of clean sodium and 750 g. (55 ml.) of mercury (Section 11,50,7, Method 1), and warm it to 50° in a 500 ml. Pyrex bottle. Add a cold suspension of 25 g. of xanthone in 175 ml. of rectified spirit, stopper the bottle and shake vigorously raise the stopper from time to time to release the pressure. The temperature rises rapidly to 60-70°, the sohd xanthone passes into solution, and a transient blue colour is developed. After about 5 minutes the alcoholic solution is clear and almost colourless. Shake for a further 10 minutes, separate the mercury, and wash it with 15 ml. of alcohol. Filter the  [c.964]

The use of selective P-antagonists for treatment of CHF has included the P -blocker metoprolol (Table 1) and results of clinical trials suggest long-term beneficial effects. Selective P -antagonists have also been tested, an example of which is xamoterol [81801 -12-9], C2 H25N20, which is (i)-A/-(2-hydroxy-3-(4-hydroxyphenoxy)propylamino)ethylmorphine-4-carboxamide. Xamoterol exhibits approximately 50% of the activity of isoproterenol, and serves to provide modest inotropic effects (128,129).  [c.129]

UV spectra, 3, 599 xanthone synthesis from, 3, 840 Xanthydryl chloride xanthone synthesis from, 3, 840 Xanthyletin synthesis, 3, 743, 804 Xanthylium laser dye synthesis, 3, 865 Xanthylium salts aromaticity, 3, 641 charge density calculations, 3, 576 C NMR, 3, 592 H NMR, 3, 585 mass spectra, 3, 620 reactions  [c.924]

See pages that mention the term Xamoterol : [c.428]    [c.405]    [c.405]    [c.442]    [c.558]    [c.964]    [c.965]    [c.117]    [c.1075]    [c.534]    [c.536]    [c.94]    [c.924]    [c.386]    [c.28]    [c.223]    [c.248]   
The organic chemistry of drug synthesis Vol.4 (1990) -- [ c.28 ]