Untersuchungen an 1,3-Thiazinen, 18. Mitt. Darstellung von 3-Amino-2-thioxo-tetrahydro-1,3-thiazin-4-onen,neuartigen cyclischen Dithiocarbazidsäureestern

1,3-Thiazines, XVIII: Preparation of 3-Amino-2-thioxotetrahydro-1,3-thiazin-4-ones, Novel Cyclic Dithiocarbazates 3-(Thiocarbazoylthio)propionic acids 1 were prepared from hydrazine derivatives, carbon disulfide and β-propiolactones. Ring closure to the novel 3-amino-2-thioxotetrahydro-1,3-thiazin-4-ones 2 was effected by different methods, mainly with acetic anhydride under acidic catalysis.     

Untersuchungen an 1,3-Thiazinen, 28. Mitt. Reaktionen von 3-Amino-2-thioxo-tetrahydro-(4H)-1,3-thiazin-4-onen mit Nucleophilen

1,3-Thiazines, XXVIII⁽¹⁾: Reactions of 3-Amino-2-thioxotetrahydro-(4H)-1,3-thiazin-4-ones with Nucleophiles 3-Amino-2-thioxotetrahydro-(4H)-1,3-thiazin-4-ones 1 are cleaved by nucleophiles preferentially at the N-3-C-4-bond. With some nitrogen bases under forced conditions cleavage of the S-1-C-2-bond also occurs yielding thiosemicarbazides.     

Untersuchungen an 1,3-Thiazinen, 33. Mitt.1) Oxidationen an Thiourethanen, 7. Mitt.2). Oxidative Desulfurierung von Dithiourethanen durch salpetrige Säure und Salpetersäure

1,3-Thiazines, XXXIII¹⁾; Oxidations of Carbamothioates, VII²⁾: Oxidative Desulfurisation of Carbamodithioates by Nitrous and Nitric Acid Carbamodithioates, mainly 2-thioxo-tetrahydro-4H-1,3-thiazin-4-ones 1 , were converted to carbamothioates, mainly 5,6-dihydro-2H-1,3-thiazin-2,4(3H)-diones 2 , by nitrous and nitric acid. With cone. nitric acid additional nitration of phenyl substituents was achieved.     

1,3-thiazines, X: Attempted synthesis of fungitoxic hydrophilic 2-thioxotetrahydro-1,3-thiazin-4-ones (author's transl)

1,3-Thiazines, X: Attempted Synthesis of Fungitoxic Hydrophilic 2-Thioxotetrahydro-1,3-thiazin-4-ones Attempts to synthesize the title compounds by three different methods were not succesful. Instead, the rhodanine-5-acetic acid esters 5 were obtained in good yields from the reaction of dithiocarbamates and maleic esters. They were converted to the acids 6 . In some cases, 5 and 6 were effective against Candida albicans.     

Untersuchungen an 1,3-Thiazinen, 19. Mitt. Darstellung von und Cyclisierungsversuche mit N-monosubstituierten S-Prop-2-inyl-thiolurethanen

1,3-Thiazines, XIX: Preparation of N-monosubstituted Prop-2-ynyl Carbonamidothioates and Attempts to Cyclize these Products The preparation of novel N-monosubstituted prop-2-ynyl carbonamidothioates 1 and their aminolysis to N,N'-disubstituted ureas is described. The failure of cyclizing the thioesters to 3,6-dihydro-1,3-thiazin-2-ones 2 is reported.     

Untersuchungen an 1,3-Thiazinen, 23. Mitt. Neuartige Umwandlungen an Tetrahydro-1,3-thiazin-2-thionen mittels Thionylchlorid

Investigations of 1,3-Thiazines, XXIII: Novel Transformations of Tetrahydro-1,3-thiazine-2-thiones with Thionyl Chloride The tetrahydro-1,3-thiazine-2-thiones 1 were transformed into the 2,2-dichlorotetrahydro-1,3-thiazines 2 some of which could be isolated. They react with water to yield the tetrahydro-1,3-thiazine-2-ones 3 and with primary nitrogen bases to yield the 2-iminotetrahydro-1,3-thiazines 4 . The 2-(nitrosoimino)tetrahydro-1,3-thiazines 6 split off nitrogen to yield 3 . Compounds of type 3 can be oxidized to the sulfones 7 .     

Prodrugs nichtsteroidaler Antirheumatika, 2. Mitt.: Hydrolysegeschwindigkeit von 5-Acyloxy-1,3-dioxolan-4-onen

Prodrugs of Nonsteroidal Antirheumatic Agents, II: Rate of Hydrolysis of 5-Acyloxy-1,3-dioxolan-4-ones 5-Acyloxy-1,3-dioxolan-4-ones are already hydrolyzed under very mild conditions (pH 7.4; 37°C). The rate constants are depending on the substitution of the dioxolanone-ring and on the acyloxy-group at C-5. Between pH 2 and pH 6 neutral hydrolysis dominates. Derivatives of several nonsteroidal anti-inflammatory drugs and of α-naphthylacetic acid were investigated in this context.     

Kondensationsreaktionen von 2-Thioxo-1,3-dithiol4,5-dicarbaldehyd zu neuen Cyclohepta-1,3-dithiol-6-onen

Condensation Reactions of 2-Thioxo-1,3-dithiole-4,5-dicarbaldehyde to Novel Cyclohepta 1,3-dithiole-6-ones We describe a simple synthesis of novel cyclohepta-1,3-dithiole-6-ones 6 and 9 by base catalyzed condensation of 2-thioxo-1,3-dithiole-4,5-dicarbaldehyde 4 with differently substituted derivatives of acetone.     

Untersuchungen an 1,3-Thiazinen, 25. Mitt. Transacylierende N-Acyl-tetrahydro- und N-Acyl-dihydro-1,3-thiazin-derivate

1,3-Thiazines, XXV: Transacylating Derivatives of N-Acyltetrahydro- and N-Acyldihydro-1,3-thiazine Novel N-acyl-2-thioxo-3,4-dihydro-1,3-thiazine-4-ones 4 and N-acyl-tetrahydro-1,3-thiazine-2,4-diones 7 were preparee by acylation of the N-unsubstituted 1,3-thiazine derivatives 3 and 6 with acid chlorides. Their characteristics are compared with those of known N-acylthiazine derivatives.     

Synthesis of thieno[2,3-d]pyrimidines from 6-imino-6H-1,3-thiazine hydroperchlorates

Mechanism of ring transformation reactions starting from substituted 6-imino-6H-1,3-thiazine hydroperchlorates is depending upon the substituent in position 5 of the thiazine nucleus. Starting from 4-methylthio-2-phenyl-6-imino-6H-1,3-thiazin-5-carbonitrile hydroperchlorat various 6-substituted 5-amino-4-methylthio-2-phenylthieno[2,3-d]pyrimidines can be obtained by reaction with acceptor substituted halogenmethanes under basic conditions in an one pot synthesis.     

Untersuchungen an 1.3-Thiazinen, 34. Mitt. Oxidationen an Thiourethanen, 8. Mitt. Oxidative Desulfurierung und nitrosierende N-Desalkylierung durch salpetrige Säure oder Salpetersäure

1.3-Thiazines, XXXIV; Oxidations of Thiourethanes, VIII Oxidative Desulfurisation and Nitrosating N-Dealkylation by Nitrous or Nitric Acid Depending on the reaction conditions, 3-amino-2-thioxotetrahydro-4H-1.3-thiazin-4-ones 1 are desulfurized by nitrous or nitric acid to yield the 2-oxoanalogues 2 or in addition are dealkylated at the nitrogen atom with liberation of aldehydes and subsequent N-nitrosation to 3 .     

A new series of benzodiazepines. 1-Hydroxyalkyl derivatives of 1,3-dihydro-2H-1,4-benzodiazepin-2-ones.

A series of new 1-hydroxyalkyl derivatives of 1,3-dihydro-2H-1,4-benzodiazepin-2-ones bearing a 3-hydroxyl or a 4-N-oxide function together with some related compounds have been synthesized. Compound (22) [1-(2-hydroxyethyl)-3-hydroxy-7-chloro-1,3-dihydro-5-(o-fluorophenyl)-2H-1,4-benzodiazepin-2-one] has been selected for further studies both in animals and in humans as an antianxiety-sedative agent.     

Untersuchungen an 1,3-Dicarbonylverbindungen, 13. Mitt. Anellierte Chinoline III, 11-Oxo-5,11-dihydro-benzothieno-[3,2-b][1]chinoline

1,3-Dicarbonyl Compounds, XIII; Fused Quinolones, III: 5,11-Dihydrobenzothieno[3,2-b][1]quinolin-11-ones The S-alkylated products 4 , obtained by reaction from methylthiosalicylate with α-bromoacetophenones 2 or 3 , are converted to the 1,3-dicarbonyl compounds 5 . These compounds cyclize to yield the quinolones 6 on heating with polyphosphoric acid (PPA).     

New 1,3-benzoxazin-2-ones or thiones of molluscacidal activity

A facile synthetic approach towards 3-aryl, alkyl or beta-glucopyranosyl-1,3-benzoxazin-2-ones and their thio-analogues 3 was adopted via the reaction of the easily available 3-(2-hydroxyaryl)-2-propen-1-ones 1 with a variety of isocyanates or isothiocyanates. The isolation of the open-chain carbamates 2 and then independent cyclization to the corresponding 1,3-benzoxazines 3 confirms the reaction sequence. Molluscacidal activity of the products was screened.     

Untersuchungen an 1,3-Thiazinen, 37. Mitt. Umsetzungen NH-acider Tetrahydro-1,3-thiazinderivate mit Sulfensäure- und Sulfonsäurechloriden

Investigations on 1.3-Thiazines, XXXVII; Reactions of NH-acidic Tetrahydro-1.3-thiazine Derivatives with Sulfenic and Sulfonic Acid Chlorides N-sulfenyl derivatives were obtained from 5,6-dihydro-2H-1,3-thiazine-2.4(3H)-diones 1 and sulfenic acid chlorides in the presence of triethylamine or from the sodium salts of 1, 3. 2-Thioxo-tetrahydro-4H-1,3-thiazine-4-ones 4 were on the other hand sulfenylated at sulfur to 5 which was easily cleaved hydrolytically to 1 . N-Sulfonylation was only achieved with methane sulfonyl chloride to yield 13.     

1,3-Thiazines. IV. The constitution of the reaction products of 2-thioxo-4-oxo- and 2,4-dioxotetrahydro-1,3-thiazines with alkoxides]

The Constitution of the Reaction Products of 2-Thioxo-4-oxo- and 2,4-Dioxo-tetrahydro-1,3-thiazines with Alkoxide The reaction of alkoxide with the 2-thioxo-4-oxo-tetrahydro-1,3-thiazines 1a–d does not lead to addition products to the C = S bond, as reported in the older literature, but to the β-(amino-thiocarbonylmercapto)-propionic acid esters 4a–e , the structures of which have been confirmed by IR-spectroscopy and independent syntheses. Under the same conditions the 2,4-dioxo-compounds 5a and 5b split to the carbamic acid esters 7a and 7b and β-mercaptopropionic acid ester 8 .     

Cyanogen condensations as a route to 3-amino-2-imino-1,3-benzothiazin-4-ones with CNS depressant potential.

Seven new 3-amino-2-imino-1,3-benzothiazin-4-ones, prepared from the condensation of cyanogen and 2-mercaptobenzhydrazides, were evaluated in a neuropharmacological mouse profile. CNS depression was observed in several members of the class.     

Untersuchungen an 1,3-Dicarbonyl-Verbindungen, 20. Mitt. 3-Acyl-4,5-dihydro-5-methyl-4-oxo-pyrano[3,2-b]indole

1,3-Dicarbonyl Compounds, XX: 3-Acyl-4,5-dihydro-5-methylpyrano[3,2-b]indol-4-ones On treatment with POCl₃/DMF the BF₂ chelate 2 , obtained from the 1,3-dicarbonyl compound 1 , yields the fused 3-formyl-4-pyrone 3 . The carbinol 6 , the carboxylic acid 7 and the tetrazole 9 can be prepared from 3 .     

Untersuchungen an 1,3-Dicarbonyl-Verbindungen, 3. Mitt. Untersuchungen an β-Ketoestern

Investigations on β-Ketoesters The β-keto-ester 2b gives with thiophenol in PPA the anellated thiochromone 3b . The synthesis of the β-keto-amides 6 and 8 is described. Tautomerism and H-bonding of the 1,3-dicarbonyl-compounds 2, 6 and 8 is investigated by spectroscopic methods.     

Untersuchungen an 1,3-Dicarbonyl-Verbindungen, 23. Mitt. 3-Acyl-4-oxo-4H-[1]benzothieno[3,2-b]pyrane

1,3-Dicarbonyl Compounds, XXIII: 3-Acyl-4H-[1]benzothieno[3,2-b]pyran-4-ones Syntheses of the 3-acylpyrones 6 and 8 from the 1,3-dicarbonyl compound 1 and reactions of the products are reported.