Tetrahydro-j3-carbolines

Evidence has been put forward that 6-methoxy-l-methyl-l,2,3,4-tetrahydro-j3-carboline may be a component of animal tissues and may be identical with adrenoglomerulotrophine, a factor controlling aldosterone secretion, which is found in the pineal gland where it occurs together with 5-hydroxytryptamine... 

Partial dehydrogenation of a tetrahydro-j3-carboline derivative has been postulated to account for the origin of 7-hydroxy-l-... 

A neat, biomimetic synthesis of brevicolline (21a) employs as essential starting material the (lS,3S)-tetrahydro-j3-carboline derivative (22), which is the major... 

Tetrahydro-j3-carboline reacts with ethyl glyoxylate in acetonitrile generating azomethine ylide ( ,Z)-86. Even the extremely inert a hydrogen of pyrrolidine can be activated in the condensation with isatin leading to ylide ( ,Z)-87 (86CC602). It is surprising that pyridine-2-carbaldehyde also serves... 

The described two-step procedure is uncomplicated and can be carried out in 1 day to give in good yield a product that does not require any further purification. This procedure has been used for the preparation of 3-methyl-, 9-methyl-, and 6-methoxy-l,2,3,4-tetrahydro-j3-carboline and has been modified to obtain 9-phenyl-l,2,3,4-tetrahydro-j3-carboline. The method is generally applicable to the preparation of other 1-unsubstituted tetrahydro-/3-carbolines providing the 1-carboxylic acid precursor is not insoluble in the hot acid used to effect decarboxylation. 

A variety of j5-carboline and tetrahydro-j3-carboline compounds have come to light recently which contain either a fourth ring, or four rings and a second nitrogen, or in some cases five rings and a second nitrogen these are clearly not related to the main body of monoterpene-tryptamine alkaloids. 

The mass spectra of members of the yohimbine family (200) exhibit only the typical tetrahydro-j3-carboline fragments, but none which could be related to a fission reaction in ring E. So the steric differences in ring E are of minor importance for the fragmentation... 

The root bark yielded l-isobutyl-l,2,3,4-tetrahydro-j3-carboline (B.HCl, mp 257-259°). A synthetic specimen prepared by the condensation of tryptamine with isovaleraldehyde was identical with the natural product (89). 

Brevicarine (7) and brevicolline (8) have been interrelated by bromination of brevicarine, which affords 6,8-dibromobrevicarine, T,6,8-tribromobrevicarine, and 6-bromobrevicolline (9), also obtainable by the direct bromination of brevicolline. " The total synthesis of Na-methylbrevicolline (10) takes advantage of an ingenious new method for the synthesis of 4-substituted tetrahydro-j3-carbolines (Scheme... 

The mass spectrum of peraksine shows peaks m/e 182, 169, 168, and 156 characteristic of tetrahydro-j3-carbolines. These peaks as well as an intense peak at m/e 309 (M-1) suggested a sarpagine-like structure. 

Cl5H18N2O2, trans-l-Ethyl-3-(methoxycarbonyl)-1,2,3,4-tetrahydro-j3-carboline, 46B, 274... 

It is interesting to note that whereas 7-methoxy-1-methyl-1,2,3,4-tetrahydro-j3-carboline condenses with diazobenzenesulfonic acid to give an azo compound (presumably the 6-arylazo derivative) and 7-methoxy-l-methyl-3,4-dihydro-jS-carboline gives a bisazo compound, none of the fully aromatic jS-carboline derivatives studied by Perkin and Robinson underwent azo-coupling. 

The spectra of a number of l-oxo-l,2-dihydro-j8-carboline derivatives and l-oxo-l,2,3,4-tetrahydro-j3-carboline derivatives have also been recorded. 

Figure 5, Expected pathway to form 1-methyl-1,2,3,4-tetrahydrO j3-carboline-l,3-dicarboxylic acids (2a/b) during the natural aging process of...

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