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New Results in the Chemistry of Quasi-Aromatic Compounds.

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from acetate residues exclusively, it may be considered that
the CI unit (formaldehyde equivalent) in indole alkaloids of
the a-type is located in ring E and not in ring D [corresponding to a bridge between the CH,-groups of ( 2 ) or
( 3 ) ] . Preliminary tracer experiments seem not to preclude
this possibility [3].
A vinylogue of I-methyl-4-cyclopentadienylidene-l,4-dihydropyridine with n = 3 was obtained similarly. It is a
strongly basic, labile, blue compound.
1,2,6-Trimethyl-4-cyclopentadienylidene(or -4-indenylidene-)
1,4-dihydropyridine is a particularly good model for studying
electrophilic substitutions in quasi-aromatic systems. The
indenylidene compound (3) undergoes reactions at the 3'position: protonation gives (.?a), nitrosation yields (3b),
benzoylation leads to (3c), coupling with aromatic diazonium salts gives (Jd), and on substitution with dimethylformamide/phosphorus oxychloride one obtains (3e) ; substitution with azastreptocyanin cations also occurs at the
During attempts to convert acylalkenylamines of type (4)
and (5) [R = H or alkyl, R' = alkyl or aryl] into their hydrochlorides, they cyclized in a Pictet-Spengler-type reaction to
yield derivatives of tetrahydroisoquinoline or tetrahydro-3carboline with one o r two substituents in the I-position.
These compounds can in turn be converted into heterocycles
of the type (1)-(3) [ D . Lnudieii, Th. Rnnbe]. Dihydroresorcinol condenses with tryptamine hydrochloride to give a n
acylalkenylamine analogous to (5). Tryptaminobutenone
(5), R = H, R = CH3, reacts with acids t o form the pyridiniuni salt (6).
[GDCh-Ortsverband Muhlheini/Ruhr (Germany),
November 1 Ith, 19641
[ V B 8861195 I € ]
Ch. Jurz, Munchen (Germany)
3,4-Bis-(9'-fluorenylidenemethyl)-6-(9'-fluorenyl)fulvene was
prepared as red needles, m. p. 234.5 OC, via its anion ( I ) ,
Amax = 588 mp, log E = 4.87, from 3,4-bis-(9'-fluorenylideneprethyl)-6-dimethylaminofulvene and fluorenyl-lithium. It
moved to be the most acidic hydrocarbon known to date. In
the anion ( I ) , the negative charge can be distributed over
four cyclic 5;-sextets.
German version: Angew. Chern. 77, 224 (1965)
New Results in the Chemistry of
Quasi-Aromatic Compounds
4- p y r idinyl
(3b): Y = NOH
(3cj: Y
(3e): Y = CH-N(CH&z
Cyclopentadienylsodium or indenylsodium displace the
secondary amino group in salts of type (3e) to form intensely
colored merocyanins with a latent carbanionomethine
structure (4).
[GDCh-Ortsverband Dusseldorf (Germany),
December 7th, 19641
[VB 8871196 IE]
German version: Angew. Chern. 77, 224 (1965)
Syntheses of Heterocyclic 0- and N-Glycosides
W. Pfleiderer, Stuttgart (Germany)
Related to the 9-aminofulvenes are the deep-colored heterologues of sesquifulvapolyene. Vinylogous l-methyl-4(2)fluorenylidene-l,4(1,2)-dihydroquinolines, e.g. (Z),
made by treating the corresponding polymethine salts with
fluorene and sodium methoxide. Protonation of the 9position of the fluorenyt residue with mineral acids gives rise
to quinolinium salts.
are converted, on
direct glycosidation under the conditions described by Fischer and Helferich, into 2-amino-4-alkoxy-7-glycosyloxypteridines [ I ] . Pteridine N(S)-glycosides were not obtained,
even after varying the substituent on the pyrimidine moiety
of the 7-hydroxypteridine skeleton. 4-Dimethylamino- ( l a )
[ 2 ] , 2-amino- ( I b ) , and 2-dimethylamino-7-oxodihydropteridine ( l c ) in the form of their heavy-metal salts react
uniformly with a-acetobromoglucose to yield the 0-glycosides
(2a) -(2c).
H3C -
A g or H g salt
f 2)
n = 0, 1, 2, 3
R' = (CH,),N; R2 = H
131 Cf. the contradictory results obtained by E. Leete and S. Ghosal, Tetrahedron Letters 1962, 1179, and by A . R . Battersby,
R . Binks, W . Lawrie, G . V . Parry, and B. R . Webster, Proc. chem.
Soc. (London) 1963,369.
Angew. Chem. internat. Edit. 1 Vol. 4(1965)
R' = H; R2 = NH2
R' = H; R' = (cH,),N
1 No. 3
26 1
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chemistry, compounds, results, quasi, aromatic, new
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