Synthesen mit Alkylschwefelchloriden (VI. Mitteil. über organische Schwefelchloride)

Brintzinger, H.; Langheck, Malte

doi:10.1002/cber.19530860502

Cited by 48 publications

(10 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This must represent the equilibrium mixture reflecting the relative stability of these two isomers. Similarly, I and I1 gave acid-catalyzed equilibrium mixtures in the ratio of cis to trans of 1: 1. n/fethylsztlfenyl chloride and ethylsuljenyl chloride were prepared according t o the method of Brintzinger et al (8,9) by the reaction of sulfuryl chloride with methyldisulfideand ethyl disulfide, respectively. Benzylsulfenyl chloride was prepared by the method of Emde (10):…”

Section: Results a N D Discussionmentioning

confidence: 99%

The preparation of 3-alkylthio-2-methoxytetrahydropyrans

Baldwin¹,

Brown²

1967

Can. J. Chem.

View full text Add to dashboard Cite

The reaction of alkylsulfenyl chlorides with 3,4-dihydro-2H-pyran, follou~ed by treatment of the product with sodium methoxide, gave, highly stereoselectively, trans-3-alkylthio-2-methoxytetrahydropyrans. Purification by distillation under a vacuum a t temperatures above 55" resulted in the eliminatioll of methyl alcohol to produce 5-(a1lrylthio)-3,4-dihydro-2H-pyrans in a good yield. At lower temperatures, the more volatile homolognes could be distilled undecomposed, but these had undergone thermal isomerization t o a mixture of cisand trans-3-alkylthio-2-metho~~tetrahydropyrans. The conformational prefereilce of these isonlers is discussed.

show abstract

Section: Results a N D Discussionmentioning

confidence: 99%

The preparation of 3-alkylthio-2-methoxytetrahydropyrans

Baldwin¹,

Brown²

1967

Can. J. Chem.

View full text Add to dashboard Cite

show abstract

“…b.p. 39' at 58 rnrn (19)). Ethanesulfenyl chloride was used immediately after its preparation since on standing at room temperature it became dark red within a few hours.…”

Section: Methodsmentioning

confidence: 99%

Reaction of ethanesulfenyl chloride with 2-methoxy-5,6-dihydro-2H-pyran

Baldwin¹,

Brown²

1969

Can. J. Chem.

View full text Add to dashboard Cite

The reaction of ethanesulfenyl chloride with 2-methoxy-5,6-dihydro-2H-pyran gives only 413-chloro3a-ethylthio-213-methoxytetrahydropyran. A rationale is presented to explain the observed highly selective reaction.Canadian Journal of Chemistry, 47. 3553 (1969) Introduction Two recent reports from this laboratory (1,2) have described the reaction of alkane (or aralkane) sulfenyl chlorides with 3,4-dihydro-2H-pyran to produce trans-2-chloro-3-alkyl (or aralkyl) thiotetrahydropyran which, in the presence of sodium methoxide in methanol, gave trans-3-alkyl (or aralky1)-2-methoxytetrahydropyrans. A rationale was presented to explain the observed highly selective course of the reaction.The present communication describes the results obtained from the reaction of ethanesulfenyl chloride with 2-methoxy-5,6-dihydro-2H-pyran.

show abstract

“…n-Propyl 2-pyridyl disulphide This was first prepared by Dr. E. Ager from 2thiopyridone (Py-2-SH) and n-propanesulphenyl chloride (Brintzinger & Langhech, 1953, 1954 for use in another investigation (E. Ager, H. Suschitzky, T. Stuchbury & K. Brocklehurst, unpublished work). A saturated solution of Py-2-SH in methylene chloride was added dropwise to a stirred solution of n-propanesulphenyl chloride (prepared from 22.2g of n-propanethiol) in methylene chloride (300ml) until the orange colour disappeared.…”

Section: -Py-s-s-2-pymentioning

confidence: 99%

Characterization of the papain active centre by using two-protonic-state electrophiles as reactivity probes. Evidence for nucleophilic reactivity in the un-interrupted cysteine-25-histidine-159 interactive system

Shipton¹,

Brochlehurst²

1978

Biochemical Journal

View full text Add to dashboard Cite

1.2,2'-Dipyridyl disulphide (2-Py-S-S-2-Py) and n-propyl 2-pyridyl disulphide (propyl-S-S-2-Py) were used as two-protonic-state reactivity probes to investigate the active centre of papain (EC 3.4.22.2).2. The existence of a striking rate optimum at pH approx. 4 in the reaction of papain not only with the symmetrical probe but also with the unsymmetrical probe is shown to constitute compelling evidence that the thiolate ion component of the cysteine-25-histidine-159 interactive system of papain possesses appreciable nucleophilic character. It is not a necessary requirement that the probe reagent should engage the imidazolium ion of histidine-159 in hydrogen-bonding for the sulphur atom of the interactive system to display nucleophilic character. The single proton-binding site of propyl-S-S-2-Py cannot simultaneously interrupt the active-centre ion pair and provide for rate enhancement as the pH is lowered towards 4. The possible implication of this for the mechanism of papain-catalysed hydrolysis is discussed. 3. The suspected difference in the active centres of papain and ficin (EC 3.4.22.3), which could be a lack in ficin of a carboxy group conformationally equivalent to that of aspartic acid-158 of papain is confirmed. The reactivity of the papain thiol group towards both probe reagents is controlled by two ionizations with pKa close to 4 that are positively co-operative. 4. In the reaction of papain with 2-Py-S-S-2-Py. the reactivity appears to be controlled also by an addition ionization with pKa approx. 5. Possible origins of this additional ionization are discussed. K. The spectral and ionization characteristics of propyl-S-S-2-Py are reported. 6. The reagent reacts rapidly with thiol groups at the sulphur atom distal from the pyridyl ring to provide, at pH values below 9, stoicheiometric release of 2-thiopyridone. This property, together with the ability of the reagent markedly to increase its electrophilicity consequent on protonation, suggests alkyl-2-pyridyl disulphides in general as valuable two-protonic-state reactivity probes with exceptional specificity for thiol groups.

show abstract

Synthesen mit Alkylschwefelchloriden (VI. Mitteil. über organische Schwefelchloride)

Cited by 48 publications

References 1 publication

The preparation of 3-alkylthio-2-methoxytetrahydropyrans

The preparation of 3-alkylthio-2-methoxytetrahydropyrans

Reaction of ethanesulfenyl chloride with 2-methoxy-5,6-dihydro-2H-pyran

Characterization of the papain active centre by using two-protonic-state electrophiles as reactivity probes. Evidence for nucleophilic reactivity in the un-interrupted cysteine-25-histidine-159 interactive system

Contact Info

Product

Resources

About