Selective benzoylation of benzyl β-l-arabinopyranoside and benzyl α-d-xylopyranoside

1967 ◽  
Vol 45 (21) ◽  
pp. 2493-2500 ◽  
Author(s):  
T. Sivakumaran ◽  
J. K. N. Jones
Keyword(s):  
Benzoyl Chloride ◽  
Derivatives Of

Benzoylation of benzyl β-l-arabinopyranoside with 2.2 molar equivalents of benzoyl chloride gave benzyl 2,3-di-O-benzoyl-β-l-arabinopyranoside (65–70%) and benzyl 2,3,4-tri-O-benzoyl-β-l-arabinopyranoside (10–15%). Benzyl α-d-xylopyranoside, under similar conditions, gave benzyl 2,4-di-O-benzoyl-α-d-xylopyranoside (45%), benzyl 2,3-di-O-benzoyl-α-d-xylopyranoside (27%), benzyl 2,3,4-tri-O-benzoyl-α-d-xylopyranoside (15%), and benzyl 2-O-benzoyl-α-d-xylopyranoside (9%). Several new derivatives of benzyl β-l-arabinopyranoside and benzyl α-d-xylopyranoside have been prepared. These benzoates lead to the ready preparation of 4-O-substituted l-arabinose and d-xylose derivatives. These results are compared with those obtained for the selective benzoylation of hexopyranosides.

Syntheses of Enantiomeric N-(3-Hydroxy-2-phosphonomethoxypropyl) Derivatives of Purine and Pyrimidine Bases

1993 ◽  
Vol 58 (3) ◽  
pp. 649-674 ◽  
Author(s):  
Antonín Holý
Keyword(s):  
Benzoyl Chloride ◽  
Sodium Hydride ◽  
Cesium Carbonate ◽  
Amino Groups ◽  
Heterocyclic Base ◽  
Pyrimidine Bases ◽  
Derivatives Of ◽  
General Method

Methods of preparation of N-(3-hydroxy-2-phosphonomethoxypropyl) (HPMP) derivatives of (2S)- and (2R)-configuration (compounds I and XXVII, respectively) are described. The general method starts from the corresponding N-(2,3-dihydroxypropyl) derivatives which were converted either into the (R)-enantiomers XIII by reaction of the base with (R)-glycidol butyrate (XII) in the presence of cesium carbonate and subsequent methanolysis, or into the (S)-enantiomers XI by alkylation of the base with (R)-2,2-dimethyl-4-tosyloxymethyl-1,3-dioxolane (V) in the presence of the same reagent. The amino groups on the heterocyclic base in compounds XI and XIII were benzoylated by silylation followed by reaction with benzoyl chloride and the obtained N-benzoates XV and XVII on reaction with trityl chloride afforded the corresponding 3'-O-trityl derivatives XVI and XVIII. These compounds were condensed with bis(2-propyl) p-sulfonyloxymethylphosphonate (XXIII) in dimethylformamide in the presence of sodium hydride to give the fully protected diesters XXIV and XXVIII. These compounds could be selectively acid-hydrolyzed to remove the trityl group only under formation of compounds XXXV, or methanolyzed and then acid-hydrolyzed to remove the trityl and N-benzoyl groups and lead to compounds XXVI and XXX, or treated with bromotrimethylsilane to remove the trityl and 2-propyl group to give phosphonates of the type XXXI. All the three types of compounds were then converted into free phosphonates of the (S)-series (I) and the (R)-series (XXVII). Derivatives of cytosine (Ia, XXVIIa), adenine (Ib, XXVIIb), 2,6-diaminopurine (Ic, XXVIIc) and guanine (Id, XXVIId) were prepared. Condensation of the partially blocked adenine deriavtive XXXV with the tosyl derivative XXIII and subsequent deprotection afforded 9-(S)-(2,3-diphosphonomethoxy propyl)adenine (XLIII). Reaction of the same compound XXXV or its (R)-enantiomer XXXVIII with diethyl phosphonate , followed by deblocking, afforded 3'-O-phosphoryl derivatives (S)-HPMPA (XXXVII) and (R)-HPMPA (XL).

THE ALCOHOLYSIS OF TRIALKYLALKOXYSILANES: PART II. THE PREPARATION AND CHEMISTRY OF METHYL 2,3,4-TRI-O-TRI-METHYLSILYL-α-D-GLUCOPYRANOSIDE

1965 ◽  
Vol 43 (7) ◽  
pp. 2004-2011 ◽  
Author(s):  
D. T Hurst ◽  
A. G. McInnes
Keyword(s):  
Magnetic Resonance ◽  
Acetic Anhydride ◽  
Proton Magnetic Resonance ◽  
Benzoyl Chloride ◽  
Phenyl Isocyanate ◽  
High Yield ◽  
Aqueous Methanol ◽  
Trimethylsilyl Group ◽  
Acidic Catalysts ◽  
Derivatives Of

The trimethylsilyl group on the 6-position of methyl 2,3,4,6-tetra-O-trimethylsilyl-α-D-glucopyranoside is preferentially removed by methanolysis, using basic or acidic catalysts, giving methyl 2,3,4-tri-O-trimethylsilyl-α-D-glucopyranoside in high yield (>80%). Reaction of the latter with acetic anhydride, benzoyl chloride, or phenyl isocyanate produces the corresponding 6-substituted derivatives in quantitative yield. The trimethylsilyl residues from the latter compounds are hydrolyzed by 50% aqueous methanol with the concomitant formation of 6-O-acetyl, 6-O-benzoyl, or 6-carbanilate derivatives of methyl α-D-glucopyranoside in excellent yield. Chemical and proton magnetic resonance (p.m.r.) studies established the structure of methyl 2,3,4-tri-O-trimethylsilyl-α-D-glucopyranoside, and of subsequent derivatives prepared from this compound. Infrared and p.m.r. evidence is offered to support conclusions regarding the conformation of the groups or atoms attached to C6 and C5 of the glucoside residue in some of these compounds.

scholarly journals 2-Phenitidine derivatives as suitable inhibitors of butyrylcholinesterase

2013 ◽  
Vol 49 (1) ◽  
pp. 127-133
Author(s):  
Muhammad Athar Abbasi ◽  
Aziz-ur-Rehman ◽  
Muhammad Zahid Qureshi ◽  
Farhan Mehmood Khan ◽  
Khalid Mohmmed Khan ◽  
...  
Keyword(s):  
Infrared Spectroscopy ◽  
Benzoyl Chloride ◽  
Acetyl Chloride ◽  
Sulfonyl Chloride ◽  
Sodium Hydride ◽  
Alkyl Halides ◽  
H Nmr ◽  
Derivatives Of

This manuscript reports the synthesis of a series of N-substituted derivatives of 2-phenitidine. First, the reaction of 2-phenitidine (1) with benzene sulfonyl chloride (2) yielded N-(2-ethoxyphenyl) benzenesulfonamide (3), which further on treatment with sodium hydride and alkyl halides (4a-g) furnished into new sulfonamides (5a-g). Second, the phenitidine reacted with benzoyl chloride (6) and acetyl chloride (8) to yield the reported N-benzoyl phenitidine (7) and N-acetyl phenitidine (9), respectively. These derivatives were characterized by infrared spectroscopy, ¹H-NMR, and EI-MS, and then screened against acetylcholinesterase, butylcholinesterase, and lipoxygenase enzyme, and were found to be potent inhibitors of butyrylcholinesterase alone.

Synthesis, Characterization and Antimicrobial Activity of New Nucleoside Analogues from Benzotriazole

2016 ◽  
Vol 10 (3) ◽  
pp. 271-278
Author(s):  
Thanaa Al-muamin ◽  
◽  
Naeemah Al-lami ◽  
Suroor Rahman ◽  
Rana Ali ◽  
...  
Keyword(s):  
Schiff Bases ◽  
Nucleophilic Addition ◽  
Benzoyl Chloride ◽  
Antimicrobial Agents ◽  
Condensation Reaction ◽  
Nucleoside Analogues ◽  
The Novel ◽  
Ft Ir ◽  
Derivatives Of ◽  
Aromatic And Aliphatic Amines

Novel derivatives of 1-(´1, ´3, ´4, ´6-tetra benzoyl-β-D-fructofuranosyl)-1H- benzotriazole and 1-(´1, ´3, ´4, ´6-tetra benzoyl-β-D-fructofuranosyl)-1H-benzotriazole carrying Schiff bases moiety were synthesised and fully characterised. The protection of D-fructose using benzoyl chloride was synthesized, followed by nucleophilic addition/elimination between benzotriazole and chloroacetyl chloride to give 1-(1- chloroacetyl)-1H-benzotriazole. The next step was condensation reaction of protected fructose and 1-(1-chloroacetyl)-1H-benzotriazole producing a new nucleoside analogue. The novel nucleoside analogues underwent a second condensation reaction with different aromatic and aliphatic amines to provide new Schiff bases. The prepared analogues were characterised by FT-IR, 1H NMR, 13C NMR, HRMS(EI+) spectra. These analogues were tested against different bacteria to evaluate them as antimicrobial agents.

scholarly journals Tuberculostatic Derivatives of p-Aminobenzoic Acid. VI. Preparation of Amides of p-Aminosalicylic Acid (PAS) by Means of 2-Acetoxy-4-acetamido-benzoyl Chloride.

1952 ◽  
Vol 6 ◽  
pp. 176-179 ◽  
Author(s):  
Kai Arne Jensen ◽  
Grete Blok ◽  
Endre Berner ◽  
Ernst Finsnes ◽  
Jörgine Stene Sörensen ◽  
...  
Keyword(s):  
Benzoyl Chloride ◽  
Aminobenzoic Acid ◽  
Aminosalicylic Acid ◽  
Derivatives Of

scholarly journals SYNTHESIS, MOLECULAR DOCKING AND ANTIBACTERIAL EVALUATION OF SOME NOVEL N-4 PIPERIDINYL DERIVATIVES OF SPARFLOXACIN

2018 ◽  
Vol 11 (10) ◽  
pp. 415
Author(s):  
Hemanth K Sudheer Kumar ◽  
Parameshwar H
Keyword(s):  
Antibacterial Activity ◽  
Benzoyl Chloride ◽  
Docking Simulation ◽  
Binding Modes ◽  
Minimum Inhibitory Concentrations ◽  
Good Antibacterial Activity ◽  
Analysis Technique ◽  
1H Nuclear Magnetic Resonance ◽  
Derivatives Of

Objective: The present study envisage a series of sparfloxacin derivatives were synthesized (Q1-Q10) with added derivatives such as aminomethyl benzenesulfenyl, methyl (methylamino)benzenesulfenyl, amino methyl benzoyl chloride, nitromethyl benzoyl chloride, dimethyl phenylamino, methoxymethyl phenylamino, dimethyl oxopyrazol, methyl dioxopyrrolidine, methyl oxopyrrolidine, and N-Boc amino methyl methylpyrrolidine through N-Piperzinyl linkage.Methods: All the newly synthesized compounds were characterized by infrared,1H nuclear magnetic resonance, mass spectrometry, and elemental analysis technique, screened for docking stimulation to find out binding modes of synthesized derivatives with 3FV5 and 3IMW, and evaluated for in vitro antimicrobial activity.Results: From this study, it was found that the compound Q5 showed good antibacterial activity against Gram-positive (Staphylococcus aureus) and compound Q4 showed good antibacterial activity against Gram-negative (Escherichia coli) in comparison with standard drugs (ciprofloxacin and sparfloxacin). The zone of inhibition and minimum inhibitory concentrations studies performed to synthesized compounds. The correlation between experimental data (minimum inhibitory concentrations) and docking score suggests that penetration for docking simulation is good to mild in reproducing experimental orientation of these synthesized compounds.Conclusion: The analogs of sparfloxacin are suggested to be potent inhibitors with sufficient scope for further exploration.

scholarly journals Synthesis of 2,3-Dihydro-6-methyl-2-thiopyrimidin-4(1H)-one (6-Methylthiouracil) Derivatives and Their Reactions

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Mohammad Barmaki ◽  
Gulgaz Valiyeva ◽  
Abel A. Maharramovm ◽  
Mirze M. Allaverdiyev
Keyword(s):  
Aqueous Solution ◽  
Benzoyl Chloride ◽  
Acetyl Chloride ◽  
Chloroacetic Acid ◽  
Compound I ◽  
Ethanoic Acid ◽  
Ethanol Medium ◽  
Derivatives Of ◽  
C Nmr

The synthesis and characterization of 2,3-dihydro-6-methyl-2-thioxopyrimidin-(1H)-one (I) and some of its derivatives has been performed in our lab. Ring-closing cyclization, as a result of the condensation of ethyl-3-oxobutanoate with thiourea in KOH in an ethanol medium produced 2,3-dihydro-6-methy -2-thioxopyrimidin-(1H)-one (I). The reaction of compound (I) with 2- chloroacetic acid in an alkaline KOH solution produced the carboxylate derivative, 2-(2,6-dihydro-4-methyl-6-oxopyrimidin-2-yl-thio)ethanoic acid (II). The reaction of the resulted derivative of carboxylate (II) with the salt of copper sulphate, produced a new copper salt (III). A substitution reaction between synthesized compound (I) and 2-chloroethanol in an aqueous solution of KOH, created 2-(2-hydroxyethylthio)-6-methylpyrimidin-4(3H)-one (IV). The reaction of compound (I) with 2-(chloromethyl)oxirane in the presence of an aqueous solution of KOH, resulted yielded 2-(3-chloro-2-hydroxy-propylthio)-6-methylpyrimidin-4(3H)-one (V). Sodium mercaptide compound (VI), was produced by the reaction of (I) with NaOH and then the sodium salt of 2,3-dihydro-6-methyl-2-thioxopyrimidin-(1H)-one (VI) was reacted with 2-(chloromethyl)oxirane to result in 2-((oxiran-2-yl) methyl-thio)-6-methyl-pyrimidin-4(3H)-one (VII). Different acylation reagents (acetyl chloride, benzoyl chloride) were reacted with compound (I), in dimethylformamide, acylation happens on sulfur and furnished S-acylified derivatives of (VIII-IX). All the synthesized and obtained products were confirmed by IR,1H, and13C NMR and elemental analysis.

Mechanisms for the Benzoylation of 2-Aminopyridine

1979 ◽  
Vol 32 (2) ◽  
pp. 381 ◽  
Author(s):  
LW Deady ◽  
DC Stillman
Keyword(s):  
Acetic Anhydride ◽  
Benzoyl Chloride ◽  
Relative Rate ◽  
Direct Reaction ◽  
Ring Nitrogen ◽  
Derivatives Of

Relative rate studies on ring methyl-substituted derivatives of 2-aminopyridine in pyridine solvent show that reaction with benzoyl chloride gives monobenzoyl derivatives by direct reaction on the exocyclic nitrogen (N'). The reaction is analogous to acetylation with acetic anhydride. Reaction in acetone, however, gives, except for the 6-methyl compound, N',N?-dibenzoylamino compounds, even in the presence of excess of amine. The results are shown to be consistent with ring nitrogen benzoylation (N1), followed by rapid N'-benzoylation and intramolecular benzoyl rearrangement from N1 to N'.

Sign in / Sign up

Export Citation Format

Share Document