Synthese und Reaktivität von 1,5‐Dihydro‐5‐thiaflavinen

Fenner, Helmut; Grauert, Rolf W.; Hemmerich, Peter

doi:10.1002/jlac.197819780202

Cited by 18 publications

(8 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…211 -212°C. 6,1 ia,l2-Tetrahydro-Sa-methyl-11 a-phenyl[ 1,4]henzoxazino-/3.2-h]//,4]benzoxnzine (1 f) (9). -A) 1-(2-Benzoxazoly1)ethanol: 66 g (0.6 mol) of 2-aminophenol and 60 g (0.6 mol) of d,l-lactic acid (90% in water) were heated under stirring on an oil bath to 140°C until 16.5 ml of HzO was formed (n. 4 h).…”

Section: 2'-bibenzothiazole 23mentioning

confidence: 99%

ChemInform Abstract: Photochemical Dehydrogenation, Ring Contraction, and Ring Expansion of Hydrogenated Derivatives of Benzoxazino‐benzoxazine, Quinoxalino‐quinoxaline, and Bibenzothiazole.

Tauer

Grellmann

1990

ChemInform

View full text Add to dashboard Cite

show abstract

Section: 2'-bibenzothiazole 23mentioning

confidence: 99%

ChemInform Abstract: Photochemical Dehydrogenation, Ring Contraction, and Ring Expansion of Hydrogenated Derivatives of Benzoxazino‐benzoxazine, Quinoxalino‐quinoxaline, and Bibenzothiazole.

Tauer

Grellmann

1990

ChemInform

View full text Add to dashboard Cite

show abstract

“…58. 2.27s (3H.7-CH3),2.33s(3H,8-CH,), 3.70s(3H, 10-CH3),7.38s Chlor-2,4-dioxo-2,3,4,5-tetrahydro-3,7,8,IO-tetramethylpyrimido-[S. 4-bl[l.4]benzothiazin ( …”

Section: A-chior-24-dioxo-2345-tetrahydro-78 Io-trimethyl-pyrimentioning

confidence: 99%

Eine neue Synthese von 5‐Thiaflavin‐Derivaten

Fenner

Grauert

Tessendorf

1981

Archiv der Pharmazie

Self Cite

View full text Add to dashboard Cite

lO-Alkylpyrimido[5.4-b][ 1.4]benzothiazine 10 (5-Thiaflavine) entstehen aus den durch Umsetzung von Anilinouracil-Derivaten 3 mit SOCI, erhaltenen 4a-Chlor-pyrimidobenzothiazinen 8 durch Reduktion mit Hydrazin. Die als Intermediarprodukte bei der Bildung von 8 postulierten Sulfoxide 6 lassen sich auch aus 8 durch Hydrolyse erhalten. Erneutes Einwirken von SOCI, auf 6 fuhrt wieder zu 8. Als Nebenprodukt dieser zu einheitlichen Isomeren fuhrenden Thiaflavin-Synthese entsteht das Pyrimido[4.5-b]indol 9, fur dessen Entstehen die Zwischenstufe des 5-Chloruracils 5 plausibel ist. 1,4]benzothiazines 10 (5-thiaflavines) were prepared by hydrazine reduction of 4a-chloropyrimidobenzothiazines 8 formed from the anilinouracils 3 with SOCI,. The postulated intermediates of this reaction, the sulfoxides 6, were prepared by hydrolysis of 8. Reaction of 6 with SOCI, yields 8. In addition to 8, the pyrimidoindoles 9 are formed by cyclization of the 5-chlorouracils which arise in the chlorination of 3. A New Synthesis of 5-Thiaflavine Derivatives lO-Alkylpyrimido[5,4-b][

show abstract

“…Reactions of N ‐substituted phenyl uracilyl sulfides 42 (obtained from substituted aminobenzenethiols and bromochlorouracils) in ethanol or DMF underwent the Smiles rearrangement and cyclization to 10‐substituted 1,3‐diazaphenothiazine‐2,4(1 H ,3 H )‐diones 43 in excellent yield (75–93%) [37]. On the contrary, phenyl uracilyl sulfide 44 in acetic acid or in alcohol with hydrochloric acid underwent cyclization without the rearrangement (Scheme ) [38, 39].…”

Section: Introductionmentioning

confidence: 99%