The Morphine Alkaloids

Though the Knorr-Horlein formula was generally accepted until 1923, difficulties were frequently encountered in explaining reactions of the morphine alkaloids by it, and in some cases led to suggestions for its modification. Knorr and Horlein adopted an ethylenic linkage at C to because (1) positions C and must, for the reasons given above, be... 

Szantay C, Dornyei G and Blasko G (1994) The morphine alkaloids. The Alkaloids, Chemistry and Pharmacology (ed Cordell GA) Vol 45. Academic, San Diego, pp 127-232. 

Both raw and cooked opium contain alkaloids. These alkaloids can be extracted from the opium to produce opium derivatives for legal pharmaceuticals or for illegal consumption, such as morphine and heroin. The morphine alkaloid content, which ranges from 8% to 12%, determines the quality of the opium... 

The spectrum ofcancentrine was interpreted primarily by comparison with the previously discussed spectra of cularine and the morphine alkaloids, particularly codeine. The assignments of C-10, C-15, C-16, and the NCH3 of cancentrine followed by analogy from the corresponding carbon atoms of codeine and were confirmed by the off-resonance spectrum. The high-field... 

In the laboratory and associated greenhouse, we gave particular attention to the biosynthesis of the morphine alkaloids.12"14 At first we purchased Papaver somniferum seeds and grew splendid poppies, but they contained no morphine... 

Studies related to other derivatives of the morphine alkaloids include the receptor-binding480 and narcotic effects481 of naloxone 6-hydrazone the effects of... 

Reticuline is also the source of the morphine alkaloids by ortho/para radical coupling. The roles of the two rings are reversed this time and it is quite difficult to see at first how the structures are related. 

K. W. Bentley, The Chemistry of the Morphine Alkaloids, p. 186. Oxford Univ. Press, London and New York, 1954. 

T. K. Adler, Current Trends Heterocyclic Chem., Proc. Symp., Canberra, 1957 pp. 151-157. Academic Press, New York, 1958. K. W. Bentley, The Chemistry of the Morphine Alkaloids. Oxford Univ. Press, London and New York, 1954. 

Most phenanthrene alkaloids are easily synthesized by degradation of the corresponding aporphines. Many phenanthrenes were first prepared as aporphine derivatives for characterization or in the course of structural studies, and only later were they found in nature. Although the ready availability of most aporphines from natural sources makes this strategy very simple, it often does not constitute a formal total synthesis, and some approaches from simpler compounds have been published (29,105). Degradation of the morphine alkaloid thebaine (151) gives rise to a number of unnatural phenanthrenes (93,94,102, 104,113). 

The first series of compounds assayed directly by CD detection were the morphine alkaloids. They were supported in aqueous solutions, in a chiral cholesteric liquid crystal solvent, and mixed in pellet form with solid KBr. ° Contrary to expectations, the homogeneous aqueous solution medium gave the best selectivity among 10 related opiates and the most quantitative results. The pH-dependence of phenol substituted analogs, which in some instances caused the sign of the CD signal to invert, enhanced the selectivity. Heroin was assayed both directly and as the morphine hydroly-sate.f Direct multicomponent analyses were made for prepared mixtures of morphine, codeine, thebaine, noscapine, and opium extracts. ... 

Semi-Synthetic Transformations of the Morphine Alkaloids Although it has been synthesised (ref 61), (now by four distinct routes) morphine (63), a powerful analgesic is readily available from the natural source, opium obtained from Papaver somniferum as the major alkaloid present (approx. 10%) and indeed the first to be isolated by Serturner in 1803, while the methyl ether, codeine (64) which comprises only 0.5% is relatively weakly active. Thebaine (65) a third component of opium is non-analgesic but is important as an intermediate for the formation of codeine, a somewhat scarce commodity (ref. 62) but a valuable mild analgesic and anti-tussive in great demand. It is best prepared from morphine by methylation with phenyl trimethylammonium ethoxide the by-product consisting of dimethylaniline (ref.63). 

K.W. Bentley, The ChemistiY of the Morphine Alkaloids, Oxford University Press, London, 1954, p., 59. 

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