Compounds xiii

If X is an alkyl group and Y = H, the reference compound XIII is a straight chain hydrocarbon, and the second process above consists in its transformation to a branched unit (XIV) having a single substituent. Hence... 

No rules are available for estimating the heats of formation of the structural units of the last four examples given in Table XXV. However, it is a reasonable assumption that variations in the nature of the substituent affect the reference compound XIII and the structural... 

Compound (XIII) exists as a mixture of monomeric and dimeric species at room temperature. The same situation is true for the reaction products from methyl- and isopropyl-thiocyanate, respectively, with triisopropylborane, whereas the iminoborane obtained from reacting methyl-thiocyanate with tri-n-butylborane is dimeric 3 . With the exception of (XIII) these compounds have not been characterized by analysis. 

XIII). Compound (XIII) is added to aqueous methanol then small amounts of hydrochloric acid are added to produce dobutamine hydrochloride (XIV). 

As shown in Scheme 7, the polymerization of bis(4-fluorophenyl) phenyl-phosphine oxide (BFPO) with bisphenols [XIII] was carried out, and thermal properties of the obtained polyethers [XIV-A (ffinh = 0.63 dl/g) and XIV-B i)inh = 0.48 dl/g)] were studied by DSC and TG (12). In this study, 2,2-bis(4-hydroxyphenyl) propane and 4,4 -dihydroxybiphenyl were used as compounds XIII s. 

In Wright s opinion the existence of the transient compound,(XIII) is proved by the formation of substance (IX) which can be isolated from the products when cyclonite undergoes nitrolysis of the P and R bonds. 

Ferrocenylphosphine-gold complexes, 225 Formaldehyde oligomerization, 332 Formic acid, transfer hydrogenation, 123 Formulas, chiral compounds, xiii-xvii Four-dimensional chemistty. See Asymmetric catalysis... 

In a similar way the diethylamino group in the reaction product of N,N -dimethylurea and tris(diethylamino) phosphane, compound XIII (6), was reacted with PCl. The product,however, was compound XIV. 

The metallonitroxides, such as compound XIII, were obtained by spin-... 

Conceptually similar photoaffinity labeling experiments have been reported by Schraders laboratory quite recently (70). These workers have sought to label the cytosolic progesterone receptor of chick oviduct using the polyunsaturated synthetic progestin, R5020, Compound XIII. 

The successful preparation of isomers IX and X as well as the different reactivities of the chlorine atoms in the two rings of compound VIII and different tendency to hydrolysis shown by the methoxy groups in compound XIII provide further evidence in favour of an unsymmetrical structure of the azoxy group, in accordance with Angeli s view. 

Figure 1. Reversed phase TLC of penicillins (a) and cephalosporins (b and c). In (a) the mobile phase is represented by 2% acetone-buffer (A) Benzylpeni-cillin (B) Phenoxymethylpenicillin (C) Methicillin (D) Ampicillin (E) Carbene-cillin (F) Oxacillin (G) Cloxacillin (H) Dicloxacillin (I) Phenethicillin (J) Metampicillin (K) Naf cillin. In (b) and (c) the mobile phase is represented by 10% buffer and acetone-buffer. The compounds indicated are listed in Table III. Compound V (bis) corresponds to acid cephaloram. In (c) Compound XIII is no longer detectable since it migrated with the solvent front.

Incorporation of natural amino acids (114, 115,116, 117, 118) and homologs (119,120,121) without further chain lengthening (VII to XVI) proceeds with retention of the a-amino nitrogen (119, 120, 122). An enzyme catalyzing the oxidation and decarboxylation of the N-hydroxyamino acid VIII to the aldoxime XI (123,124) has been purified 1400-fold (125). It is stimulated by FMN, O2 uptake is observed, and the a-keto acid oxime V is not used as a substrate (124,125). Decarboxylation may occur via the a-nitroso acid IX. Incorporation of the nitro compound XIII (126) presumably occurs via the acf-nitro compound XII which was suggested by Ettlinger and Kjaer (72) as an intermediate. The addition of thiols to... 

Tonnesen HH, Skrede G, Martinsen BK. Photoreactivity of biologically active compounds. XIII. Photostabibty of mefloquine hydrochloride in the sobd state. E)rug Stab 1997 1 249-253. 

A quite different result is obtained when the reaction conditions are modified. For example, when compound XIII is taken up in hot benzene containing a catalytic amount of -toluenesulfonic acid, not only is an oxazoline obtained in which the absolute configuration of the unsymmetrical carbon (starred atom of Scheme 14.3) in the starting aziridine is retained (only 1% inversion), but the structurally isomeric oxazoline XV is produced also. ... 

This resolution (1927) showed that the salt must have the constitution XIII, and furthermore that the five-membered ring system of XIII was more stable than the six-membered ring system of XIV because the compound XIII was formed to the apparently complete exclusion of the compound XIV. This was moreover the first decisive example of a carbon atom becoming asymmetric by the operation of a coordinate link 17, 30). 

In the low [NaOAc] range, decomposition of the acetoxypalladation adduct would be fast. The proportion of compounds (XIII) and (XV) would depend on the relative rates of formation of compounds (XII) and (XIV), and the product distribution would be kinetically controlled. At high [NaOAc], the rate of decomposition of compounds (XII) and (XIV) would be inhibited, and they would have the opportunity to come to an equilibrium distribution. In this case the product distribution would be equilibrium controlled. 

Leitch, L. C. Synthesis of organic deuterium compounds. XIII. The mechanism of the Nef reaction. Synthesis of ethanal-1-d. Can. J. Chem. 1955, 33, 400-404. 

Cytotoxic activities of compound XIII against UACC 375 melanoma cancer cells ... 

Remko, M., and J. Polcin. 1981. MO investigations on hgnin model compounds. XIII. Model studies of hydrogen bonds formed in the systems hgnin-cellulose and lignin-hemicellulose. Z. Phys. Chem. (Weisbaden), 125(2) 175-181. 

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