Eine neue Arbeit �ber den Gesang der V�gel

Braun, Fritz

doi:10.1007/bf01551768

Cited by 4 publications

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“…A mixture of 1.0 g (4.16 mmoles) of 17 [18] and 4.2 mmoles of 2a (1.55 g), 2b (1.61 g), 11a (1.5 g) or 11b (1.56 g) in 40 ml of CH 2 Cl 2 containing 10 ml (0.5 M) of LiOH solution was stirred at r.t. for 12-24 h (TLC). Following the same procedure and workup were used in the general procedure, compounds 19, 20, 22a and 22b were obtained.…”

Section: Reaction Of Tetramethylthiuram Disulfidementioning

confidence: 99%

An Approach to Biologically Important S‐Heterocycles, Dithiocarbamyls, and Their Relevant Phosphono Derivatives.

2005

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The feasibility of insertions of carbanions between two sulfur atoms has been reported when 5-(4-chlorophenyl)-4-cyano-1,2-dithiol-3-thione (1) and tetramethylthiuram disulfide (17) were allowed to react with unsaturated 2a,b and active phosphonium salts 11a,b. The reactions afforded, mainly, 1,3-dithiols 4a,b and 14a,b together with substituted thiophenes 10a,b and 16a,b. Reactions of 1 and 17 with α-alkylthiomethyl phosphonates 24a,b afforded the phosphonates 25a,b and 26a,b, respectively.J. Heterocyclic Chem., 42, 103 (2005).Literature reports the synthesis and utility of many thiol and dithiol derivatives as insecticides, fungicides and seed protectants [1][2][3] as well as being useful as antioxidants and in volcanization processes [4]. In addition, they are known to possess therapeutic values in controlling diseases, such as pneumonea [5]. For these reasons, the chemistry of the sulfur-sulfur bond continues to be an active area of research from both a mechanistic and a synthetic point of view. The mechanism of nucleophilic attack by carbenoids, carbenes and phosphorus ylides on the S-S linkage in dithiols, followed by substitution reaction at the heteroatomic center (S, N, …etc), has been a major point of interest for research in the last three decades [6,7]. For the past few years, one of our research directions has centered on the synthesis of thiols, dithiols and phosphorylated sulfur compounds, derived from the reactions of acyclic and cyclic cis-disulfides with P(III) and P(V) reagents [8]. Preliminary results in a screening assay of selected synthesized compounds showed pesticidal and pharmacological activity. The work described in this article involved the reactions of 5-(4-chlorophenyl)-4-cyano-1,2-dithiol-3-thione (1) and tetramethylthiuram disulfide (17) with unsaturated-2a,b and active-11a,b phosphonium salts as well as the phosphonate carbanions 24a,b. The reactions, depicted in Schemes 1-7, led to the synthesis of the title compounds: new S-heterocycles, dithiocarbamyls and their phosphono derivatives, for biological evaluation. The results are compared and discussed, together with other published researchs in this area.Reaction of 1,2-dithiol (1) with vinyltriphenylphosphonium bromide (2a, 2 molar amounts) in a mixture of 40 ml of dimethylformamide (DMF) and 10 ml of LiOH (0.5 M) yielded 6-(4-chlorophenyl)-5-cyano-2-methyl (4H)-1,3-dithiacyclohexene-4-thione (4a, 43%) and 5-(4-chlorophenyl)-6-methyl-(4H)-4-oxothienothiapyran (10a, 21%) (Scheme 1). The products 4a and 10a were obtained in similar ratio, irrespective of the number of mole equivalents of 2a that was used.The formation of 4a and 10a could be attributed to initial attack by the carbanion center of 2a on the cleaved -S-S-linkage, initiated by the alkaline medium [6c,e]. This attack led to the formation of zwitterion 3a, which, subsequently, could follow two different pathways: i) Intramolecular cyclization and hydrolysis yielding 4a with concomitant elimination of triphenylphosphine oxide. Similar insertion reaction has been reporte...

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Section: Reaction Of Tetramethylthiuram Disulfidementioning

confidence: 99%

An Approach to Biologically Important S‐Heterocycles, Dithiocarbamyls, and Their Relevant Phosphono Derivatives.

2005

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“…containing some impurities. These esters (4.2 g) were stirred with 0.5N NaOH (50 ml, 25 Reaction of amine 16 (2.6 g) with oxirane 18 (1.36 g) at 165°C in a sealed glass tube for 6 h gave 3.16 g (82%) of diethyl2-(2-cyclohexyI-2-hydroxyethy1)aminononanedioate (24) as a yellow oil, Rf 0.40 and 0.45 (Silica, CHCI,-MeOH, 50: 1, two diastereomers) which was converted, as above, to 0.65 g (22%) of (~))-3-(2-Cyclohexyl-2-hydroxyerhyl) Reaction of amine 16 (5.18 g) and the iodoester 19 (6.48 g) by a similar procedure to that used for obtaining 26 gave 6.4 g (70%) of dierhyl2-(4ocetoxy-4-cyclohe.ryIburylamino)nonanedioare (25) as a tan oil, Rf 0.8 (H20-saturated EtOAc), which was converted as above to 3.2 g (56%) of (f)-3-(4-Cyclohexyl-4-hydroxybutyI)-2,S-dioxod- By a similar procedure to that used for the preparation of 26, reaction of amine 16 (13.1 g) with the brosylate 21 (19.1 g) and LiCl(4.5 g) in ethanol (40 ml) gave 8.1 g (40%) of dierhyl 2-[2-(1 -hydroxycyclohepryl)erhyl]aminononanedioare (27) as a yellow oil, Rf 0.3 (silica, ether-hexane 3:l). This was converted as above (see preparation of 9) to 3.1 g (42%) of (k)-3-[2-(l-hydroxycyc1ohepryl)…”

Section: (*)-(S*r*) 3-(3-cyciohexyl-3-hydro~buryl)35-dioxo-4-imidazmentioning

confidence: 99%

Synthesis and Inhibitory Activity on Platelet Aggregation of 13′‐Aza and Other ω‐Chain Modified BW245C Analogues

Barraclough

Brockwell

Caldwell

et al. 1994

Archiv der Pharmazie

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BW245C analogues which have 15'-keto, -oximino, -sulphinyl, -sulphonyl, -methyl, -1-adamantyl, 14'-hydroxy, 16'-hydroxy, 13'-14'-NH=CH, -NH-CH2, or -NH-CO groups have been synthesized and evaluated for their activity in inhibiting platelet aggregation and for their cardiovascular actions: the 13'-aza analogues 13 and 14 are more potent inhibitors of human platelet aggregation than BW245C (0.3, 0.6 and 0.2 x PGI2, respectively) and these inhibitory activities on platelet aggregation increase on incubation in vitro. The prostaglandin mimetic properties of 13 (BW68C) and 14 (BW361C) were studied in more detail and their platelet inhibitory and vasodilatory effects found to be of longer duration than those of BW245C. All other modifications to the omega-chain of BW245C led to less potent or inactive compounds.

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“…When homoxylylene dibromide is treated with aniline, it yields W-phenyltetrahy dr oiso quinoline. With dimethylamine a quaternary bromide is obtained (12).…”

mentioning

confidence: 99%

The Chemistry of Isoquinolines.

Manske¹

1942

Chem. Rev.

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Eine neue Arbeit �ber den Gesang der V�gel

Cited by 4 publications

References 0 publications

An Approach to Biologically Important S‐Heterocycles, Dithiocarbamyls, and Their Relevant Phosphono Derivatives.

An Approach to Biologically Important S‐Heterocycles, Dithiocarbamyls, and Their Relevant Phosphono Derivatives.

Synthesis and Inhibitory Activity on Platelet Aggregation of 13′‐Aza and Other ω‐Chain Modified BW245C Analogues

The Chemistry of Isoquinolines.

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