Unknown Constitution

The two following alkaloids of unknown constitution have been recorded for Berberis and Mahonia species —... 

Two ketones of unknown constitution have been isolated from natural musk. Of these, muskone, CjgH gO (or Cj Hg O), occurs to the extent of 0 5 to 2 per cent. It is a thick, colourless oil with a very powerful odour of musk. It boils at 327° to 330° at 752 mm., and at 142° to 143° at 2 mm. It yields an oxime melting at 46° and a semi-carbazone melting at 133° to 134°. 

On warming, or on treatment with ether, the solvated complex give a black pyrophoric material of unknown constitution. 

The more important triphenylmethane dyes probably date from 1834, when Runge obtained red compounds of unknown constitution from crude phenol and from crude aniline. Shortly after Perkin s discovery of mauveine (section 6.6.1) in 1856 Natanson obtained the triphenylmethane dye magenta from crude aniline by oxidation. Although many related dyes were made empirically over the following two decades, it was not until 1880 that Fischer was able to establish structural relationships within this group of dyes. The essential triphenylmethane ring system was identified by its conversion (Scheme 6.28) into 4,4,4,-triaminotriphenylmethane (6.160), the source of pararosaniline (6.161 Cl Basic Red 9). 

Reactions of butenylidene-bis-phosphonium salts with PCl3/triethyl-amine under similar conditions proceeded predominantly via base-induced fragmentation to triphenyl phosphine and polymeric products of unknown constitution (Scheme 2). Monocyclic bis-phosphonio-phospho-lides formed only as spectroscopically detectable but hardly isolable byproducts [18, 19]. 

Ammino-derivatives op Cobalt Salts—Cobaltous Salt Ammines—Cobaltic Salt Ammines—Mononuclear Cobalt-ammines containing One Atom of Cobalt in the Molecule—Cobaltic Salts with Trivalent Cation—Cobalt-ammines Containing Divalent Cation—Cobalt-ammines containing Monovalent Cation—Cobalt-ammines consisting of Non-dissociable Complex— Cobalt-ammines containing Monovalent Anion—Cobalt Salts containing Trivalent Anion—Polynuclear Cobalt-ammines containing Two or more Cobalt Atoms in the Molecule—Cobalt-ammines of Unknown Constitution— Ionisation Metamerism—Polymerisation Isomerism—Valency Isomerism —Co-ordination Position Isomerism—Isomerism due to Asymmetric Cobalt Atoms. 

Xaa symbol for an amino acid of unknown constitution in peptide formula... 

The spectral properties of ethylene oxides are among the most important, not only for the information derivable from them concerning tbe intimate structure of the three-merabered oxide ring, but also in connexion with the detection and identification of this function in complex molecules of unknown constitution, e.g. natural product. The present review is concerned with the following three types of gpectroBoopy A) infrared spectroscopy, ( ) ultraviolet spectroscopy, and ( 7) nuclear magnetic resonance spectroscopy,... 

Bromination of ethylene oxide vu reported as early as 1862 by Wurtz18 7 to give a red solid of unknown constitution. Maas and Boomer1081 obtained the same red solid on warming to room temperature oxonium complexes of ethylene oxide and bromine prepared at —80°. Freezing-point results indicated for these complexes the empirical formulas CsH40 Bt and CxH 0-2Br. No explosion occurs on warming to room temperature, however. 

Finally, a single example of desulfurization, using a tertiary phosphine, to effect cluster transformation, has been reported (26) for a heterometallic nitrosyl. Reaction of complex 18 f(f/5-C5H4Me)2V2S4Fe-(NO)2] with tributylphosphine provided [(f/5-C5H4Me)2V2S3Fe(NO)2], of unknown constitution, in 80% yield. 

On hydrolysis of the phosphatides, myo-inositol monophosphate—and, from a brain phosphatide, a diphosphate—is obtained but, these products have, in most cases, not been adequately characterized, and it is not yet known whether all phospholipids contain the same myo-inositol phosphate. It has been shown169-170 that the phosphate obtained by hydrolysis of liver phosphatide171 or soybean phosphatide172 is a mixture of myo-inositol 1- and 2-phosphates. A myo-inositol phosphate, of unknown constitution, was isolated173 from liver without previous hydrolysis apparently it occurs in the free state. 

The reaction has proceeded satisfactorily with one or two benzoyl groups present,153,507 but a benzoyl group in position 1 has also been eliminated.153 The oxidation proceeds similarly when position 4 is substituted.608 Pyrazoline itself and monoalkyl- and monoaryl-pyrazolines give the corresponding pyrazoles only in small yield on oxidation with bromine.509,510 In the majority of cases bromination occurs together with oxidation, and often brominated products are the only ones isolated. Thus 1,3,5-triphenylpyrazoline yields a tribromide of unknown constitution.49 The hydro bromide of 4-bromopyrazole (43) was obtained almost quantitatively from 3-butoxy-J1-pyrazoline (42).611A mixture of 1,5-dimethylpyrazole and the 4-bromo compound... 

Crystalline diisopropylidene derivatives of unknown constitution have been obtained from d-18 and L-psicose18 and a sirupy diisopropylidene compound has been reported from D-sorbose.28... 

Degradation procedures analogeus to those used for mycobactin P (see above) showed the aromatic residue to be salicylic acid (2-hydroxy-6-methylbenzoic acid in mycobactin P) and the hydroxy acid to be (+)-( -hydroxybutyric acid ((-)-3-hydroxy-2-methylpentanoic acid in mycobactin P). Fatty acid side chains substantially different from those in mycobactin P a minor component contains a s-octadec-2-enoic acid (identical to the principal product in mycobactin P). The major substituents in the fatty acid side chain are Cis to C21 fragments of unknown constitution. 

The arbitrary classification of Rauwolfia alkaloids (91) is simplified here, and it is slightly different from a recent arrangement (92). The Rauwolfia alkaloids can all be regarded as yohimbinoid derivatives as shown in Chart I, viz. the yohimbines (all yohimbine isomers) 18-hydroxyyohimbines (reserpine-type alkaloids) ring E heterocycles and their anhydronium analogs (ajmalicine, serpentine) ajmaline-type (which includes sarpagine) and compounds of unknown constitution. 

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