Phosphorus Monothioacids Research Articles

Phosphoryl- and Thiophosphoryl Thioalkynes

Abstract Syntheses of S-alkynyl derivatives of phosphorus monothioacids with the triple bonds in the α, β, and γ positions are described. Compounds of the type R2P(O)SC≡CR′ show unusually high anticholinesterase ability (“acetylenic effect”).

Analysis of Ambident Reactivity of Alkaline Salts of Phosphorus Monothioacids

Abstract The ambident reactivity of alkaline salts of phosphorus monothioacids in alkylation reactions has been studied. The role of structure of ambident anions and ion pairs formation was established. The alkylation rate constants of the free anions and ion pairs are calculated. For the first time the complete quantitative analysis of the ambident reactivity in the alkylation of alkaline salts of phosphorus monothioacids is presented.

ChemInform Abstract: Reaction of Sugar Epoxides with Phosphorothioic Acids, Evidence of the Pentacoordinate Phosphorus Intermediate in the Reaction of 5,6‐Anhydro‐1,2‐O‐isopropylidene‐α‐D‐glucofuranose with Phosphorothioic Acids.

AbstractThe reaction of sugar epoxides 166 such as (I) with organic phosphorus monothioacids such as (II) provides a convenient procedure for synthesizing sugar thiophosphates and mercaptosugar phosphates.

Reaction of sugar epoxides with phosphorothioic acids, evidence of the pentacoordinate phosphorus intermediate in the reaction of 5,6-anhydro-1,2-0-is0propylidene-α-d-glucofuranose with phosphorothioic acids

The reaction of sugar epoxides with organic monothioacids of phosphorus provides a convenient procedure for synthesizing sugar thiophosphates and mercaptosugar phosphates. Based on detailed analysis of intermediates and factors influencing the reactivity of phosphorus monothioacids with sugar epoxides the reaction acheme is proposed involving pentacoordinate intermediate which undergoes endo or/and exocyclic elimination. It uas -found that the reaction of 5,6-anhydro-1,2-0-isopropylidene-α-D-glucofuranose 7 with phosphorothioic acids 8a and 8b yields three types of products in equilibrium: the thiophosphates 9a and 9b , the oxathia-phospholanes 11a and 11b and the mercaptophosphates 10a and 10b . Under more drastic conditions the phosphates 10a and 10b can be converted irreversibly into the episulphide 12 and phosphoric acids 13a and 13b , reapectively. It is clearly possible that both compounds 10 and 11 can be formed from the same pentacoordinate intermediate, and the experimental evidence provides strong support for it.

Reaction of phosphorus monothio acids with oxetanes

The reaction of dialkylthiophosphoric and cyclic six and seven-membered thiophosphoric acids with oxetanes gives the S-3-hydroxyalkyl esters of these acids. During synthesis the S-3-hydroxyalkyl esters of the five-membered cyclic thioacids undergo rearrangement to the 3-mercaptoalkyl derivatives.

STEREOCHEMISTRY OF ORGANOPHOSPHORUS CYCLIC COMPOUNDS XII. A Comparative Study of the Molecular Dimensions and Conformations of Thio-1,3-2-Dioxaphospholane Rings. Crystal and Molecular Structure of the Imidazolium Salt of 2-Hydroxy-4,5-dimethyl-1,3,2-dioxaphospholane-2-sulphide

Abstract This work presents a comparative study of the geometry and conformation of the 1,3,2-dioxaphospholane ring and is part of a general investigation of the synthesis and geometrical isomerism of the cyclic five-membered phosphorus monothioacids. The following general conclusions may be drawn for the 1,3,2-dioxaphospholane derivatives. 1) the axial bond lengths P[sbnd]S and P[sbnd]O are dependent on the substitution pattern of the ring. 2) the conformation of the phospholane ring is influenced by intramolecular steric contacts. 3) hydrogen bonds from the dioxathiophospholanes contribute to the stabilization of the crystal lattices. Compound C7H13N2O3PS-cis (I) may be crystallized from a chloroform/benzene mixture. Crystal Data: orthorhombic, a = 25.284(10), b = 7.119(3), c = 12.909(6) Å, Z = 8, space group Pca2i, R = 0.078. The compound (I) contains two independent phospholane rings, the ring of one of which displays an envelope that of the second a half-chair conformation. The respective asymmetry parameters are ΔCs C(1) = 1.2 (phosphorane ring A) and ΔC2 p = 1.2° (phospholane ring B).

Synthesis of ?-substituted butynyl esters of phosphorus thioacids

1. A number ofω-chlorobutynyl esters of phosphorus monothioacids were synthesized. 2. The reaction of theω-chlorobutynyl esters of phosphorus monothioacids with nuoleophilic reagents gave a number ofω-substituted S-butynyl esters of phosphorus monothioacids.

ChemInform Abstract: GLYCOSYLATION OF ORGANIC THIO‐ AND SELENOACIDS OF PHOSPHORUS. THE REACTION OF ORGANIC MONOTHIO ACIDS OF PHOSPHORUS WITH GLYCOSYL BROMIDES. THIONO‐THIOLO REARRANGEMENT OF GLYCOSYL PHOSPHOROTHIOATES

AbstractDie Glykosylierung des Ammoniumsalzes (II) mittels des Glu Copyranosylbromids (I) führt hauptsächlich zum S‐Glucosyl‐Derivat (III) neben einer geringen Menge des O‐Glucosyl‐Derivats (IV).

ChemInform Abstract: SYNTHESIS AND ANTICHOLINESTERASE PROPERTIES OF SOME S‐BENZHYDRYL ESTERS OF PHOSPHORUS MONOTHIO ACIDS

1. Alkylation of salts of phosphorus monothio acids with diphenylbromomethane in benzene forms S-benzhydryl esters of the corresponding phosphorus monothio acids with concomitant formation of the O-benzhydryl esters (<5–7%). 2. We have examined the anticholinesterase activity of S-benzhydryl esters of phosphorus monothio acids toward human erythrocyte acetylcholinesterase (ACE) and horse serum butyrylcholinesterase (BuCE). 3. S-Benzhydryl O,O-diethyl phosphorothiolate, O-ethyl methylphosphonothiolate, and O-ethyl phenylphosphonothiolate, and diethylphosphinothiolate belong among mixed inhibitors, whereas esters of diisopropylphosphinothioic acid inhibit both enzymes only reversibly. We demonstrate that purely reversible inhibition of CE by thiolates of phorphorus acids is possible. 4. We examine the influence of the substituents on the phosphorus atom on the rate constants for ACE and BuCE inhibition.

Glycosylation of organic thio- and selenoacids of phosphorus : The reaction of organic monothio acids of phosphorus with glycosyl bromides. Thiono-thiolo rearrangement of glycosyl phosphorothioates

Ambident anions derived from phosphorus monothio acids have been glycosylated by 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl-, 2,3,4,6-tetra-O-acetyl-α-D-galactopyranosyl- and 2,3,4-tri-acetyl-α-D-xylopyranosyl bromides, yielding β-S-glycosyl- and /gb-O-glycosylthioates. The S/O ratio of the glycosylated phosphorothioates depends markedly on the salt used. Ammonium salts favour the formation of S-derivatives, whereas silver salts give mainly O-derivatives. O-Glucosyl phosphorothioate undergoes thermal isomerisation to S-glucosyl phosphorothioate, with retention of configuration at the glycosylic centre. The implications of this stereochemical result are briefly discussed.

Synthesis and anticholinesterase properties of some S-benzhydryl esters of phosphorus monothio acids

1. Alkylation of salts of phosphorus monothio acids with diphenylbromomethane in benzene forms S-benzhydryl esters of the corresponding phosphorus monothio acids with concomitant formation of the O-benzhydryl esters (<5–7%). 2. We have examined the anticholinesterase activity of S-benzhydryl esters of phosphorus monothio acids toward human erythrocyte acetylcholinesterase (ACE) and horse serum butyrylcholinesterase (BuCE). 3. S-Benzhydryl O,O-diethyl phosphorothiolate, O-ethyl methylphosphonothiolate, and O-ethyl phenylphosphonothiolate, and diethylphosphinothiolate belong among mixed inhibitors, whereas esters of diisopropylphosphinothioic acid inhibit both enzymes only reversibly. We demonstrate that purely reversible inhibition of CE by thiolates of phorphorus acids is possible. 4. We examine the influence of the substituents on the phosphorus atom on the rate constants for ACE and BuCE inhibition.

ChemInform Abstract: REACTIONS OF PHOSPHORUS MONOTHIO ACIDS WITH ALIPHATIC DIAZO COMPOUNDS

AbstractPhosphormonothiosäuren, z.B. der Art (I) 2(11), werden mit zahlreichen Diazoverbindungen (III) behandelt und die verschiedenen Alkylierungsprodukte (IV) und (V) bezüglich ihrer Anteile und ihrer Zusammensetzung untersucht.

REACTIONS OF PHOSPHORUS MONOTHIO ACIDS WITH ALIPHATIC DIAZO COMPOUNDS

Abstract Reactions of phosphorus monothio acids with diazomethane, diazoacetone, diphenyldiazomethane, and diazofluorene have been studied. The ratio of the yields of the S- and O-derivatives QS/QO has been found to be dependent on three factors: i) the nature of substituents at phosphorus - with electron-donor substituents raising the O-derivative yield and the quantity log (QS/QO) varying as εσ of the substituents; (ii) stability of alkyldiazonium and carbocation - with QO increasing with the carbocation stability; and (iii) polarity of the medium - the O-derivative yield rises with dielectric permeability of the medium and QS/QO has been found to be a linear function of 1/D. The most probable mechanism has been established as proton transfer from the acid to the diazocompound followed be formation of the S-derivative and the O-derivative. The former results from an SN2 reaction of the alkyldiazonium cation with the thiol-thione anion within the ion pair. The O-derivative arises from the thiol-thion anion and the carbocation; the latter resulting from decomposition of the alkyldiazonium cation within the ion pair.

Dissociation constants of phosphorus monothioacids in absolute ethanol and nitromethane

1. The method of potentiometric titration in transfer circuits was used to determine the dissociation constants of phosphorus monothioacids ABPSOH in abs. ethanol and nitromethane at 25°. In these solvents the thione-thiol equilibrium is shifted toward the thione forms. 2. The differentiating effect of nitromethane on the strength of the studied phosphorus monothioacids was established.

Infrared spectra and structures of salts of phosphorus monothioacids

Infrared spectra and structures of salts of phosphorus monothioacids