6-hydroxy homologues

Treatment of the oxazole (699) with ammonia converts it into 5-hydroxy-4,6-dimethyl-pyrimidine (700) and homologues may be made similarly 60CB1998). 

CHsjOH. CHlCgHg). CH(COOH). CH. COOH COOH. CHlCgHg). CH(CHaOH). CH. COOH COOH. CH(C2Hg). CH(COOH). CH. CH OH AomoPilopic acid is very stable, and is probably therefore the y-lactonic acid of one of these three hydroxy-acids. Further, pilopic acid seems to be produced from its higher homologue by loss of carbon dioxide and oxidation of the contiguous carbon atom. Of the four y-lactonic acids derivable from these three hydroxy-acids only two (I and II) answer these conditions,... 

Quaternary salts of the substances represented by tliese formulae have been prepared by Kogl, Veldstra and van der Laan as well as of the next lower homologues, the substituted butyraldehydes, and the methyl ethers of both series. Their pharmacological activities were negligible in comparison with that of muscarine, but as six stereoisomeric forms may be produced in each synthesis, the inactivity may be due to stereoisomerism, just as in the case of threonine (a-amino-)3-hydroxy-butyric acid) where West and Carter found that only the d —) form is... 

Whereas condensation of a-hydroxy ketones such as benzoin and acetoin on heating with formamide [240] or ureas in acetic acid [239, 242] to form imidazoles such as 769 or 770 is a well known reaction, only two publications have yet discussed the amination of silylated enediols, prepared by Riihlmann-acyloin condensation of diesters [241], by sodium, in toluene, in the presence of TCS 14 [241, 242]. Thus the silylated acyloins 771 and higher homologues, derived from Riihl-... 

Hydroxy-perhydropyrimido[2,l- ][l,4]oxazine 287 was obtained in 38% yield from 3-(2-hydroxyethyl)-l,3-propa-nediamine and glyoxal in aqueous solution. A small amount of the pentacyclic 319 also formed. Using acetaldehyde the 9-Me homologue formed in 56% yield, without the pentacyclic compound <1996H(43)1991>. 

The Bostrychid Dinoderus bifoveolatus is a serious pest on cassava, the dried roots of manioc. Again, this species shows male specific volatiles, two of which were found to produce intense signals in the antennae of conspecific males and females. The minor component proved to be (3R,5S,6R)-3,5-dimethyl-6-hy-droxyoctan-2-one 116, while the major one was shown to be its homologue, (4R,6S,7R)-4,6-dimethyl-7-hydroxy-nonan-3-one 117 [235]. 

As discerned from Table 9, the photoproduct ratios from irradiation of neat 77 vary drastically among homologues and with temperature for the n = 7 member, Unlike the n-alkanones discussed previously, the cyclic diones must be intrinsically bent as shown in the ORTEP drawings in Figure 43. Since the C=0- H, distance in each case is <3.0 A, excitation of the molecules should result in formation of hydroxy-1,4-biradicals. The fate of those radicals depends upon the flexibility of the reaction cavity and its free volume. The results indicate that sufficient free volume is present in the reaction cavities to allow topochemical conversion to photoproducts, but not... 

Literature data on the carbon skeleton elongation may be classified according to the number of carbon atoms added. Such a classification, although far from being ideal, is useful from the synthetic viewpoint. Scheme 2 illustrates the usefulness of a-amino acids (in particular a-amino-(3-hydroxy acids e.g., serine, threonine, and their homologues) in the synthesis of amino sugars. 

The diethyl compound without the iodine is 2,5-dimethoxy-N,N-diethylamphetamine, which was prepared by the reductive alkylation of DMA with acetaldehyde and sodium cyanoborohydride. This product, DEDMA, was a clear white oil, bp 82-92 °C at 0.15 mm/Hg which did not form a crystalline hydrochloride. An interesting measure of just how different these N,N-dialkylated homologues can be from the psychedelic primary amines, pharmacologically, can be seen in the published report that the beta-hydroxy derivative of DEDMA is an antitussive, with a potency the same as codeine. 

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