bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lipophilic α‐hydroxybenzylphosphonates as prodrugs of 3′‐azido‐2′,3′‐dideoxythymidine (AZT)
Authors: Meier Chris , Habel Lothar W. , Balzarini Jan , De Clercq Eric 
Published: July 2007

AbstractThe α‐hydroxybenzylphosphonates 1a–1j of the antiviral drug 3′‐azido‐2′,3′‐dideoxythymidine 5 (AZT) as potential lipophilic prodrugs were readily accessible in 49% to 87% yield via a four‐step synthetic pathway introducing the modifications in the aromatic ring system in the last step by making use of intermediate 6. All compounds 1a–1j exhibited higher partition coefficients in 1‐octanol/water than AZT (5). In hydrolysis studies at pH 7.5 we observed that precursors to bioactive compounds were delivered by simple hydrolysis of the lipophilic precursors 1a–1j via two different mechanisms: the phosphonate‐phosphate rearrangement leading to the benzylphosphotriesters 2 and/or the direct cleavage into the di‐AZT phosphonate 6. Both compounds 2 and 6 were further degraded yielding the potentially antiviral active compounds 4 and 8, respectively. The hydrolysis pathway could be controlled by the substitution pattern in the benzylic moiety. Identical hydrolytic behavior of 1 was detected in „biological”︁ hydrolysis kinetics by using a RPMI culture medium containing 10% heat‐inactivated fetal calf serum (FCS). The title compounds 1a–1j exhibited considerable HIV‐1 and HIV‐2 activity in wild‐type CEM/O cells.
Synthesis of anacardic acids
Authors: Zehnter Reinhard , Gerlach Hans 
Published: July 2007

AbstractThe anacardic acids 1–11, isolated from various plants, were synthesized by a new general method. Reaction of the methyl alkynoates 12–18 with 1‐methoxy‐1,4‐cyclohexadiene at 200°C afforded directly the methyl 2‐methoxybenzoates 19–25 with long chain substituents in 6‐position in 74–85% yield. The dienophiles 12–16 were prepared by pyrolysis of the corresponding acylphosphoranes 26–30, the dienophiles 17 and 18 by methoxycarbonylation of the corresponding alkynes 31 and 32 via the hydroxy esters 33 and 34. Demethylation of 19–23 with All3 gave the methyl salicylates 35–39 which could be hydrolized to the anacardic acids 1–4 and 7. Hydrolysis of 24 and 25 provided the hydroxy acids 40 and 41, which were converted by treatment with CBr4/PPh3 into the acids 42 and 43 bearing bromoalkyl side chains. These were transformed into 44–47 by reaction with 1‐hexynyllithium and 1‐octynyllithium. Stereoselective hydrogenation of 44–47 gave 48–51 with (Z)‐alkene side chains. In a similar approach 42 was converted into 52 and then into 53, which gave upon treatment with 1‐pentynylmagnesium bromide or 1‐heptynylmagnesium bromide the acids 54 and 55 with alkadiyne side chains. Stereoselective hydrogenation provided 56 and 57 with (Z,Z)‐alkadiene side chains. The 2‐methoxy group in 48–51, 56, 57 was demethylated by treatment with All3 to give the anacardic acids 5, 6, 8–11.
Synthesis of [1.1.1]Propellanes by Bridging of Bicyclo[1.1.0]butanes
Authors: Werner Markus , Stephenson David S. , Szeimies Günter 
Published: July 2007

AbstractSeveral [1.1.1]propellanes were synthesized by bridging the 1,3‐positions of the corresponding bicyclo[1.1.0]butane. The synthesis of 1‐bromo‐3‐(chloromethyl)bicyclobutanes and the bridging were carried out in a one‐pot reaction by addition of 2.0 equiv. of MeLi to 1,1‐dibromo‐2,2‐bis(chlormethyl)‐cyclopropanes 10. Three routes to 10 were investigated: Firstly, the Wittig reaction of 1,3‐dichloroacetone leading to (chloromethyl)allyl chlorides 6 was, with the exception of 6m, successful only with Wittig reagents derived from primary alkyl halides, Secondly, reduction of diethyl alkylidenemalonates with LiAlH4 in benzene afforded carbinols 12 which were converted into 6 by reaction with N‐chlorosuccinimide/dimethyl sulfide. The cyclopropanation of 6 to 10 was achieved by reaction with bromoform/NaOH under phase‐transfer catalysis conditions. Finally, starting from diethyl alkylidenemalonates, the sequence of reduction and cyclopropanation could be interchanged, according to the sequence 11 → 13 → 14 → 10. Propellanes 5b and 3 were reduced with LiAlH4 to bicyclo[1.1.1]pentanes 15b and e. 2‐D INADEQUATE NMR spectra of 5d and 5p indicate that the coupling constants J(13C‐13C) between the bridgehead positions are very small, i.e. 0.47 and 0.53 Hz, respectively.
van‐der‐Waals‐Komplexe, Intermediate monomolekularer Reaktionen
Authors: Roth Wolfgang R. , Hunold Frank 
Published: July 2007

van der Waals Complexes, Intermediates in Unimolecular ReactionsThermolysis of rac‐ and meso‐1,1′,2,2′,3,3′ ‐hexamethyl‐1,1′‐biindenyl and (1E, 5E)‐1,3,4,6‐tetraphenyl‐1,5‐hexadiene in supercritical CO2 in the presence of oxygen allows to identify three types of intermediates, the free radicals (2 and 5) and the equilibrating complexes I and II consisting of radical pairs. From the oxygen dependence of the trapping and rearrangement rates it is shown, that the complex I is the primary thermolysis product, which in contrast to the complex II does not react with oxygen. The temperature dependance of these rates allows to calculate the enthalpy well of the complex II, which agrees well with predictions of our reaction force field.
Asymmetrische Elektrophile α‐Amidoalkylierung, 11. Neue chirale Hilfsgruppen aus (+)‐Camphersäure
Authors: Wanner Klaus TH. , Paintner Franz F. 
Published: July 2007

Asymmetric Electrophilic α‐Amidoalkylation, 11. – New Chiral Auxiliaries from (+)‐Camphoric AcidHerrn Professor Eberhard Reimann mit den besten Wünschen zum 60. Geburtstag gewidmet.
The chiral bicyclic carboxylic acids 3b–e have been prepared in a few steps from camphoric acid. They were designed as new chiral auxiliaries for asymmetric synthesis with chiral N‐acyliminium ions featuring precomplexation as a mechanism for asymmetric induction. Their asymmetric induction was evaluated in alkylation reactions with the enamides 5b–e being performed by addition of HCl and subsequent treatment of the resulting α‐chloro amide with AlEt3. The carboxylic acid 3e turned out to be well suited as a chiral auxiliary providing high asymmetric induction (e.g. 92.9/7.1 with ZnEt2) and moderate chemical yields (66% 12e + 13e) and being easily removed by acid hydrolysis without destruction.
New Synthetic Pathways to Nitrogen Heterocycles
Authors: Laschat Sabine 
Published: July 2007

AbstractNovel Lewis acid‐catalyzed cyclizations of N‐arylimines and N‐benzylimines derived from amino acids and terpenes allow the diastereoselective preparation of octahydroacridines, indolizino[3,4‐b]quinolines, indolizidines, quinolizidines and piperidines. Although these two types of reactions can be classified as formal hetero‐Diels‐Alder and hetero‐ene reactions respectively, both proceed stepwise via cationic intermediates, which allow stereochemical control via chelate complexes. Stereochemical and mechanistical studies are described briefly.
A Stable Thiazol‐2‐ylidene and Its Dimer
Authors: Arduengo Anthony J. , Goerlich Jens R. , Marshall William J. 
Published: July 2007

AbstractThe synthesis, characterization and X‐ray crystallographic structure determination are described for a stable thiazol‐2‐ylidene 2. This thiazol‐2‐ylidene is the first example of a stable, crystalline carbene in which the singlet carbene center bears a sulfur substituent. The carbene 2 is the closest stable analog of the important thiamin (vitamin B1) carbene. Although the thiazol‐2‐ylidene 2 is sufficiently stable to isolate at room temperature in the absence of moisture and oxygen, it will dimerize to form a normal carbene–carbene dimer {2}2. With the isolation and structure determination of both 2 and {22}, this system is the first in which a stable carbene and its corresponding dimer have been isolated and characterized. Additionally reported is the “reduced” 2H‐thiazoline 2 · H2 in which the former carbene center in 2 has been reduced to a methylene (CH2) group. Thiazol‐2‐ylidenes with smaller groups on nitrogen (e.g. mesityl or methyl) are too unstable to allow easy isolation. The dimer from 3,4,5‐trimethylthiazol‐2‐ylidene possesses a very unusual geometry in which one of the former carbene centers is planar while the second is pyramidal.
Cycloadditions, 25. – Synthesis and Reactions of sec‐N‐Aryl‐2‐methyl‐2,3‐butadienamides
Authors: Himbert Gerhard , Schlindwein Hans‐Jürgen 
Published: July 2007

AbstractThe reaction of 2‐methyl‐2,3‐butadienoyl chloride 1 with the N‐aryl‐ or the N‐hetarylamines, 2a–f and 2g, h, respectively, in the ratio 1 : 2 (or 1 : 1 in the presence of triethylamine) furnishes the corresponding allenamides 3a–h, accompanied by the HCl adducts, the 3‐chloro‐2‐methyl‐3‐butenamides 4a–g, or the 3‐butynamide 5h. Heating of the allenamides bearing a benzenoid (3a–e) or thiophene (3h) nucleus does not generate any defined products; only the amides bearing the 1‐naphthyl (3f) and the furfuryl (3g) moiety undergo an intramolecular Diels‐Alder reaction to give the oligocyclic compounds 6 and 7. However, heating of the benzenoid allenamides 3a–c in the presence of tolyl isocyanate furnishes, via the N‐carbamoyl‐amides 10a–c, the intramolecular Diels‐Alder products 11a–c, whereby the monocyclic arene has functioned as diene. Reaction of 1 with the 2‐aminofuran derivative 2i leads directly to the Diels‐Alder product 9, a 2 : 1 adduct, whereby the initially formed amide 3i and the intramolecular Diels‐Alder product 8 are not isolated.
Balanced Decarboxylation of Aromatic Polyacids – A One‐Step Synthesis of Perylene‐3,4‐dicarboxylic Anhydride
Authors: Langhals Heinz , von Unold Petra , Speckbacher Markus 
Published: July 2007

AbstractPerylene‐3,4‐dicarboxylic anhydride (3) is prepared from technical grade perylene‐3,4:9,10‐tetracarboxylic anhydride (1) in 25% yield by a partial decarboxylation reaction using noncondensing amines. Perylene‐3‐carboxylic acid (4) and perylene‐3,4‐dicarboxylic imide (5) are prepared in the same way in yields of 24% and 76%, respectively, by a variation of the reaction conditions.
Highly Selective Alkylation of 5‐Amino‐1‐methyl‐1H‐1,2,4‐triazole with 1‐(1‐Chloroalkyl)pyridinium Chlorides under Formation of Novel Geminal Bis(heteroarylium) Salts: A Combined Experimental/MO‐Theoretical Study
Authors: Anders Ernst , Wermann Kurt , Wiedel Bernd , Eynde Jean‐Jacques Vanden 
Published: July 2007

Abstract1‐[(5‐Amino‐1‐methyl‐1H‐1,2,4‐triazol‐4‐ylium)(alkyl/aryl)‐methyl]pyridinium dichlorides 3a–h [geminal bis(heteroarylium) salts] were synthesized in high yield from 5‐amino‐1‐methyl‐1H‐1,2,4‐triazole (6a) and the 1‐[(alkyl/aryl)chloromethyl]pyridinium chlorides 1a–h under mild, neutral conditions. Analogous reactions of 1a and 1d with the isomeric 3‐amino‐1‐methyl‐1H‐1,2,4‐triazole (6b), carried out to support the spectroscopic analysis of the alkylation products 3a–h, likewise show exclusive alkylation at the N‐4 atom of the 1H‐1,2,4‐triazole ring with formation of the isomeric 1‐[(3‐amino‐1‐methyl‐1H‐1,2,4‐triazol‐4‐ylium)arylmethyl]pyridinium dichlorides 4a and 4d, respectively. Semiempirical MO and ab initio methods have been applied to predict the relative energies of isomers of 6, the activation barriers of the reaction of electrophiles with 6, and the relative energies of some product salts.
Zinc‐Mediated Asymmetric Epoxidation of α‐Enones
Authors: Enders Dieter , Zhu Jiqun , Kramps Laurenz 
Published: July 2007

AbstractA new efficient method for the asymmetric epoxidation of α‐enones with oxygen in the presence of diethylzinc and a chiral amino alcohol is presented. The epoxidation proceeds in moderate to excellent yields, complete diastereoselectivity and enantiomeric excesses of up to >99% by using enantiomerically pure (1R,2R)‐N‐methylpseudoephedrine 7 as a chiral additive. The amino alcohol auxiliary 7 employed can be almost completely recovered with unchanged enantiomeric purity.
Tris(1‐naphthyl)borane Studied by Laser Flash Photolysis, Matrix Isolation, and Low‐Temperature NMR Spectroscopy: Two Isomers with Significantly Different Triplet Excited State Properties
Authors: Bucher Götz 
Published: July 2007

AbstractLaser flash photolysis (308 nm) of tris(1‐naphthyl)borane (TNB, 1) in cyclohexane solution yields a transient spectrum that is best interpreted as the superposition of the spectra of two transient species with λmax = 460 nm (transient 1, τ = 10 μs) and λmax = 640 nm (transient 2, τ = 20 μs). Transient 2 also shows some absorption at λ > 800 nm. Both transient species exhibit behaviour typical of triplet excited states. The seemingly paradoxical situation of two long‐lived triplet excited states being generated by excitation of a single compound can be resolved in terms of two isomeric structures of TNB. The activation energy for isomerization is very low and has been calculated (AM1/RHF) to be of the order of 2.7 kcal/mol. Further evidence comes from low‐temperature 1H‐NMR spectroscopy. At T = 183 K, some NMR bands of 1 are significantly broadened, while the shape of other bands remains nearly constant. This indicates that the broadening effect observed is due to the slowing‐down of an intramolecular rearrangement, and not to a general increase in solvent viscosity. The phosphorescence spectrum of 1, matrix‐isolated in Ar at 10 K, consists of three bands, which can be attributed to two different emitting isomers. The corresponding triplet energies differ significantly and are 57.8 and ca. 48 kcal/mol, respectively. The LFP experiments performed with 1 gave no evidence for the formation of the hypovalent boron species 1‐naphthylborene or di‐1‐naphthylboryl radical.
1,4‐cis‐Diaminotetra(di)deoxyheptitols from Tropilidene – a Variable Access to Tropa‐Type Heterocycles
Authors: Falk‐Heppner Manuela , Hugger Uwe , Keller Manfred , Kaiser Clemens , Krieger Richard , Fritz Hans , Prinzbach Horst 
Published: July 2007

AbstractThe synthetic potential of the dianhydrocycloheptenepentols 3 and dianhydrocycloheptaneheptols 4 – ultimately available from tropilidene – as intermediates en route to 1,4‐cis‐diaminotetra(di)deoxyheptitols is studied. With standard bivalent N nucleophiles (methyl‐, benzylamine, hydrazines) the regioselective installation of two (e.g. 9, 34) amino functions has to compete with the generation of variously functionalized tropa‐type 8‐azabicyclo[3.2.1]octanes (e.g. 29, 30, 35, 45, 47). With azide (N) as monovalent nucleophile in unsaturated diepoxides 3 twofold, nearly regiospecific substitution (7) – in competition with [3,3]‐sigmatropic migration (SN2′ substitution) –, in saturated diepoxides 4 regioselective monosubstitution (39) can be achieved.
The First Total Synthesis of Praecoxin B and Pterocarinin C, Two Natural Products of the Tannin Class
Authors: Khanbabaee Karamali , Lötzerich Kerstin 
Published: July 2007

AbstractEnantiomerically pure diphenic ester 3 was obtained by esterification of acyl chloride 2 with the glucose derivative 1 by kinetic resolution. Hydrolysis of the ester 3, acylation of the free OH groups at C‐4 and C‐6 of the diol 4 with acid 5 followed by irradiation led to the anomerically deprotected α‐ and β‐anomers (7) (4:1). The natural product praecoxin B (8) was obtained by hydrogenative debenzylation. A second member of the ellagitannin group pterocarinin C (11) was obtained from the common intermediate 7 by acylation in the anomeric position to 10 followed by debenzylation.
Physarorubinic acid, a polyenoyltetramic acid type plasmodial pigment from the slime mold Physarum polycephalum (myxomycetes)
Authors: Nowak Alexander , Steffan Bert 
Published: July 2007

AbstractThe polyenoyltetramic acid physarorubinic acid (2) has been isolated from microplasmodia of the slime mold Physarum polycephalum. The structure was elucidated by means of 1D‐ and 2D‐NMR, IR, and UV spectroscopy and mass spectrometry. The stereochemistry was proven by synthesis of the tetramic acid unit and application of circular dichroism. It was shown that plasmodia of a white mutant strain also contain yellow pigments.
Substrate‐Directed Diastereoselective Hydroformylations, 1. Substrate‐Directed Diastereoselective Hydroformylation of Methallylic Alcohols – Development of an Efficient Catalyst‐Directing Group for Rhodium‐Catalyzed Hydroformylation
Authors: Breit Bernhard 
Published: July 2007

AbstractThe development of an efficient catalyst‐directing group based on ortho‐diphenylphosphanyl benzoate (o‐DPPB) for the substrate‐directed, diastereoselective hydroformylation of methallylic alcohols 5 is described. The hydroformylation of methallylic o‐DPPB esters 9 provides the corresponding syn‐aldehydes 10 with diastereoselectivities of up to 96:4. A specific steric demand of the substituent at the stereogenic center of the methallylic derivatives 9 was found to be necessary to achieve a high degree of stereoselectivity. Experiments have been performed that prove that the o‐DPPB group acts as a catalyst‐directing group by reversibly coordinating to the catalyst. The removal of the o‐DPPB group was accomplished by means of alkaline hydrolysis, thereby furnishing the lactols 6. Oxidation of 6 provides the corresponding γ‐lactones 7.
Aziridine‐2,2‐dicarboxylates: Synthesis, Reactions, and Photochromism
Authors: Schirmeister Tanja 
Published: July 2007

AbstractDimethyl 3‐[(4‐nitro)phenyl]aziridine‐2,2‐dicarboxylate (3a) represents a new, photochromic aziridine. 3a and related aziridines undergo cycloadditions with dipolarophiles to form five‐membered heterocycles and react with nucleophiles with cleavage of the C2C3 bond.
Synthesis of 4,5‐Disubstituted 1H‐1,3,4,5‐Tetrahydrobenz[cd]indole Derivatives
Authors: Galambos Géza , Csókási Pál , Szántay Csaba , Szántay Csaba 
Published: July 2007

AbstractTetrahydrobenz[cd]indole derivatives (51–54) were synthesized from 4‐iodo‐3‐(2′‐nitroethyl)indole (10) via palladium‐catalysed coupling with acetylenes followed by a thiol addition, an oxidation and an intramolecular Michael‐addition.
Investigations on Solid‐Phase Peptide Synthesis in N‐to‐C Direction (Inverse Synthesis)
Authors: Henkel Bernd , Zhang Lianshan , Bayer Ernst 
Published: July 2007

AbstractThe possibility of peptide assembly in the N‐C direction by using HOBt salts of the amino acid 9‐fluorenylmethyl esters has been investigated. The first amino acid derivative has to be coupled with the N‐terminus to the polymer‐bound trityl linker. Determination of the loading with the first amino acid derivative could be carried out according to the same method as for Fmoc‐amino acids on the resin. Kinetic measurements were made of both the coupling of the amino acid derivatives during chain elongation, and the cleavage of the peptide from the resin. Several C‐terminally modified peptides were synthesized with chain elongation being monitored by UV as it is standard practice in peptide synthesis in the usual direction. Particular attention was paid to racemization that may possibly occur.
Two‐ and Three‐Dimensional Tetrathiafulvalene Macrocycles
Authors: Nielsen Mogens Brøndsted , Becher Jan 
Published: July 2007

AbstractThe syntheses and some physical properties (redox potentials) of cyclic tetrathiafulvalenes (TTF) are reviewed. The ring closure is generally performed in one of two different ways: (i) by coupling of 1,3‐dithiol derivatives thereby forming the central fulvene bond, or (ii) by cyclization of a preformed TTF derivative. The second route is very efficient when using the cyanoethyl protection/deprotection method and has made possible the preparation of a number of two‐ and three‐dimensional macrocycles, e.g. mono‐, bis‐ and tetramacrocycles, oligomeric macrocycles and cage‐type molecules. The use of tetrathiafulvalenophanes in supramolecular chemistry is also exemplified in this microreview.
Synthesis of Enantiomerically Pure Cyclopropyl Boronic Esters
Authors: Luithle Joachim E. A. , Pietruszka Jörg 
Published: July 2007

AbstractThe synthesis of enantiomerically pure cyclopropyl boronic esters 12a−d and 13a−d has been achieved. The high‐yielding process involves the condensation of readily available alkenyl boronic acids 1a−d with (2R,3R)‐1,4‐dimethoxy‐1,1,4,4‐tetraphenyl‐2,3‐butanediol (10), Pd(II) acetate catalyzed cyclopropanation with diazomethane, and chromatographic separation of the diastereoisomers. The absolute configuration has been determined by converting 12a−d and 13a−d to the corresponding cyclopropanols (1R,2R)‐4a+b/(1R,2S)‐4c+d and (1S,2S)‐4a+b/(1S,2R)‐4c+d, respectively, compounds that allowed correlations to be made with previously published data.
A DFT Study on the Vinylcyclopropanecarbaldehyde‐to‐2,5‐Dihydrooxepin Hetero‐Cope‐type Rearrangement and on Related Reactions
Authors: Sperling Dirk , Reißig Hans‐Ulrich , Fabian Jürgen 
Published: July 2007

AbstractThe prototypical 1,2‐cis‐vinylcyclopropanecarbaldehyde‐to‐2,5‐dihydrooxepin hetero‐Cope‐type rearrangement was studied by “exact” first‐principle methods. The reaction pathway was examined. The reaction, as well activation energies, was calculated for the unimolecular transformation of vinylcyclopropanecarbaldehyde and various derivatives. The derivatives differ from vinylcyclopropanecarbaldehyde by replacement of the formyl (CHO) by the thioformyl (CHS) or formiminyl (CHNH) group and, in part, by replacement of hydrogen atoms at the substituted carbon atoms of the cyclopropane ring by hydroxyl or formyl substituents. The experimental reaction parameters of vinylcyclopropanecarbaldehyde are surprisingly well reproduced by B3LYP/6‐31G* density functional and MP2/6‐31G* ab initio quantum theoretical calculations. Reactant and product are nearly isoenergetic, while the activation energy amounts to about 25 kcal/mol. In the case of the nitrogen and sulfur containing compounds the isomeric seven‐membered ring structures are considerably favoured over the cyclopropanes. Due to a low calculated activation energy a rapid formation of the 2,5‐dihydrothiepin is expected. Substitution of the hydrogen at the substituted ring carbon atoms in vinylcyclopropanecarbaldehyde by OH and CHO also lowers the barrier and increases, in general, the exothermicity of the reaction. As shown by the reaction energies of isodesmic reactions both reactants and products are stabilized by substitution. However, the seven‐memberd ring compounds are more strongly stabilized than the cyclopropanes. The OH group exerts a different effect depending on whether the linkage is geminal or vicinal to the CX group. The difference is caused by hydrogen bond formation in geminal arrangements. The substituent effects in the cyclopropane series parallel those for the prototypical Cope‐type and Claisen‐type series. The particular feature of the cyclopropane series is the lower stability of the cyclopropanes relative to the corresponding open chain congeners. This is obviously due to the ring strain which over‐compensates for attractive interactions between cyclopropane and the substituents. In consequence, the formation of seven‐membered ring compounds proceeds more easily than the formation of the corresponding compounds in related Cope‐type rearrangements.
Amidine‐Induced Ring Transformation of a Substituted 1,1‐Dioxo‐1,2‐thiazine‐4‐carbaldehyde into New Pyrimidine Derivatives
Authors: Fanghänel Egon , Bartossek Hagen , Baumeister Ute , Hartung Helmut 
Published: July 2007

AbstractAs a masked 1,3‐dicarbonyl compound, the 1,1‐dioxo‐2H‐1,2‐thiazine‐4‐carbaldehyde 1 undergoes ring transformation with amidines to produce 2‐substituted 4‐methyl‐5‐[1‐methyl‐2‐methylthio‐2‐(N‐phenylsulfamoyl)vinyl]pyrimidines 3a–f. For 3b, an X‐ray structure analysis is reported. From the 4‐methyl‐2‐methylthio‐5‐[1‐methyl‐2‐methylthio‐2‐(N‐phenylsulfamoyl)vinyl]pyrimidine (3e), the substituted pyrimidinone 4 is obtained by acidic hydrolysis.