Thiohydantoins. II. Thiohydantoins Derived from Aspartic and Glutamic Acids

1952 ◽  
Vol 5 (4) ◽  
pp. 721
Author(s):  
JM Swan
Keyword(s):  
Acetic Anhydride ◽  
Carboxylic Acids ◽  
Ammonium Thiocyanate ◽  
Derivatives Of ◽  
Isomeric Pairs ◽  
Acyl Derivatives

N-Acyl derivatives of the &carboxylic acids, aspartic and glutamic acids, yield the corresponding anhydrides when heated with acetic anhydride in the presence or absence of ammonium thiocyanate. In general these anhydrides form isomeric pairs of amides and anilides, and only one of each pair can be converted into the corresponding 2-thiohydantoin. The anhydrides from N-phenylacetyl- and N-p-nitro-benzoylglutamic acids, and N-acetylaspartic acid have been regarded hitherto as oxazolones.

Studies in Thiohydantoin Chemistry. I. Some Aspects of the Schlack-Kumpf Reaction

1996 ◽  
Vol 49 (5) ◽  
pp. 541 ◽  
Author(s):  
BM Duggan ◽  
RL Laslett ◽  
JFK Wilshire
Keyword(s):  
Amino Acids ◽  
Acetic Acid ◽  
Acetic Anhydride ◽  
Ammonium Thiocyanate ◽  
Sodium Thiocyanate ◽  
Side Chains ◽  
Derivatives Of

An investigation has been carried out into the Schlack-Kumpf reaction, i.e., the reaction of amino acids with a mixture of acetic anhydride, acetic acid and sodium thiocyanate (occasionally ammonium thiocyanate was used). Particular emphasis was placed on the reactions with amino acids containing sensitive or functional side chains, i.e., serine, threonine , arginine , proline , lysine, histidine , cysteine , and aspartic and glutamic acids. The reaction of serine, and of certain of its O- and N-substituted derivatives, takes an unusual course to give an acetylated thiohydantoin derivative of cysteine. Correspondingly, threonine gives an acetylated thiohydantoin derivative of β- methylcysteine. Similar reactions occurred with the 3-phenylthiohydantoin derivatives of serine and of threonine to give acetylated thiohydantoin derivatives of cysteine and of β-methylcysteine respectively.

Thiohydantoins. I. The Preparation of Some 2-Thiohydantoins from Amino Acids and Acylamino Acids

1952 ◽  
Vol 5 (4) ◽  
pp. 711 ◽  
Author(s):  
JM Swan
Keyword(s):  
Amino Acids ◽  
Acetic Anhydride ◽  
Ammonium Thiocyanate ◽  
Acyl Derivatives ◽  
Degradation Of Peptides

A reinvestigation of the stepwise degradation of peptides and proteins by the Schlack and Kumpf (1926) procedure, which involves conversion of the terminal carboxyl residue to a 5-substituted-2-thiohydantoin; has been undertaken. The following amino acids or their aoetyl derivatives have been converted by warming with acetic anhydride and ammonium thiocyanate into the corresponding 1-acetyl-2-thio-hydantoins: valine, methionine, isoleucine, α-aminophenylacetic acid, tryptophane, histidine, and tyrosine. These new 1-acetyl-2-thiohydantoins, as well as others, have been deacetylated by an improved procedure. Certain 1-acyl-5-carbethoxy-2-thio- hydantoins on hydrolysis give 2-thiohydantoin only. N-acetylthreonine, acetic anhydride, and ammonium thiocyanate produce 5-ethylidene-2-thiohydantoin, also obtained by the condensation of acetaldehyde with 2-thiohydantoin or its 1-acyl derivatives, or from the interaction of ammonium thiocyanate with 2-phenyl-4-ethylideneoxazol-5-one. This type of rearrangement occurs in other cases.

Stereochemical studies. VIII. Further studies of stereochemical effects on the course of oxidation of α-acyloctahydronaphthalenones

1980 ◽  
Vol 33 (11) ◽  
pp. 2467 ◽  
Author(s):  
S Middleton ◽  
LE Stock
Keyword(s):  
Hydrogen Peroxide ◽  
Carboxylic Acids ◽  
Derivatives Of ◽  
Acyl Derivatives

trans-Fused octahydroindene-1- and -2-carboxylic acids are formed stereoselectively on oxidation of α-acyl derivatives of trans-fused octahydronaphthalen-1(2H)- and -2(1H)-ones by hydrogen peroxide.

Studies on enolate chemistry of 8-thiabicyclo[3.2.1]- octan-3-one: enantioselective deprotonation and synthesis of sulfur analogs of tropane alkaloids

2001 ◽  
Vol 79 (11) ◽  
pp. 1792-1798 ◽  
Author(s):  
Marek Majewski ◽  
Marc DeCaire ◽  
Pawel Nowak ◽  
Fan Wang
Keyword(s):  
Acetic Anhydride ◽  
Key Words ◽  
Carboxylic Acids ◽  
Alkylating Agents ◽  
Tropane Alkaloids ◽  
Lithium Amides ◽  
Lithium Enolate ◽  
Unsaturated Carboxylic Acids ◽  
Derivatives Of ◽  
Enantioselective Deprotonation

Enantioselective deprotonation of 8-thiabicyclo[3.2.1]octan-3-one (1) with chiral lithium amides, followed by reactions with electrophiles affords sulfur analogs of tropane alkaloids of pyranotropane family. Thus, deprotonation of 1 with (S)-N-(diphenyl)methyl-1-phenylethylamine (11d), followed by the reaction of the resulting nonracemic enolate with benzaldehyde gives the corresponding aldol product as one diastereoisomer (exo, threo) and in high enanatiomeric purity (95% ee). Trimethylsilyl chloride, acetic anhydride, and acyl cyanides react readily with the lithium enolate to give the corresponding derivatives of 1, however common alkylating agents fail to provide C-alkylated products. The reaction with acyl cyanides derived from α,β-unsaturated carboxylic acids (e.g., cinnamoyl cyanide) can be utilized in synthesis of thia-analogs of tropane alkaloids physoperuvine and isobellendine (13, 15).Key words: enantioselective deprotonation, tropane alkaloids.

Substituent effects of phosphorus and arsenic containing groups in aromatic substitution. VI. Orientation in nitration of some anilides and phenyl esters

1976 ◽  
Vol 54 (4) ◽  
pp. 560-565 ◽  
Author(s):  
Tomasz A. Modro ◽  
Jerzy Pioch
Keyword(s):  
Acetic Anhydride ◽  
Substituent Effects ◽  
Aromatic Substitution ◽  
Phosphorylated Compounds ◽  
Derivatives Of ◽  
Acyl Derivatives ◽  
Meta Isomer

The orientation in nitration of N-acyl derivatives of aniline and O-acyl derivatives of phenol in aqueous H2SO4 and in acetic anhydride has been studied. Acetyl and methanesulfonyl derivatives are exclusively ortho/para directing, whereas the N- and O-phosphorylated compounds yield in both media considerable amounts of the meta isomer. The observed differences in orientation are discussed in terms of different protonation sites and strong πp−πd interactions of the oxygen or nitrogen and the P(IV) atom.

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