Direct conversion of tetrahydropyranylated alcohols to the corresponding bromides

Wagner, Alain; Heitz, Marie-Paule; Mioskowski, Charles

doi:10.1016/s0040-4039(00)95252-3

Cited by 61 publications

(19 citation statements)

References 6 publications

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“…The latter was converted to bromide 20 in 76% yield by CBr 3 -triphenylphosphine reagent. This reagent is not compatible16 with acid-labile groups like THP but inclusion of triethylamine in the reaction mixture successfully removed this obstacle. This modification may significantly expand use of the reagent.…”

Section: Resultsmentioning

confidence: 99%

Phosphonate analogues of cyclopropavir phosphates and their E-isomers. Synthesis and antiviral activity

Mhaske

Ksebati

Prichard

et al. 2009

Bioorganic & Medicinal Chemistry

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Z-and E-phosphonate analogues 12 and 13 derived from cyclopropavir and the corresponding cyclic phosphonates 14 and 15 were synthesized and their antiviral activity was investigated. The 2,2-bis (hydroxymethylmethylenecyclopropane acetate (17) was transformed to tetrahydropyranyl acetate 18. Deacetylation gave intermediate 19 which was converted to bromide 20. Alkylation with diisopropyl methylphosphonate afforded after protecting group exchange (21 to 22) acetylated phosphonate intermediate 22. Addition of bromine gave the dibromo derivative 16 which was used in the alkylation-elimination procedure with 2-amino-6-chloropurine to give Z-and E-isomers 23 and 24. Hydrolytic dechlorination coupled with removal of all protecting groups gave the guanine phosphonates 12 and 13. Cyclization afforded the cyclic phosphonates 14 and 15. Z-Phosphonate 12 was a potent and non-cytotoxic inhibitor of human and murine cytomegalovirus (HCMV and MCMV) with EC 50 2.2-2.7 and 0.13 μM, respectively. It was also an effective agent against EpsteinBarr virus (EBV, EC 50 3.1 μM). The cyclic phosphonate 14 inhibited HCMV (EC 50 2.4-11.5 μM) and MCMV (EC 50 0.4 μM) but it was ineffective against EBV. Both phosphonates 12 and 14 were as active against two HCMV Towne strains with mutations in UL97 as they were against wild-type HCMV thereby circumventing resistance due to such mutations. Z-Phosphonate 12 was a moderate inhibitor of replication of herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) but it was a potent agent against varicella zoster virus (VZV, EC 50 2.9 μM). The cyclic phosphonate 14 lacked significant potency against these viruses. E-isomers 13 and 15 were devoid of antiviral activity.

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Section: Resultsmentioning

confidence: 99%

Phosphonate analogues of cyclopropavir phosphates and their E-isomers. Synthesis and antiviral activity

Mhaske

Ksebati

Prichard

et al. 2009

Bioorganic & Medicinal Chemistry

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“…76,77 An extension of this approach has been achieved using CBr 4 /Ph 3 P with oxetane and oxolane homologues yielding α,ω-dibromo compounds, as described in a previous report. 22 The [Ph 3 P(CBr 3 )] + Br − brominating agent is milder than reagents used in traditional methods, 22,61,78 such as HBr/HOAc or PBr 3 . 79−81 Oxetane 2 was thus subjected to 2 equiv of CBr 4 /Ph 3 P in lieu of the aforementioned reagents to avoid possible complications.…”

Section: ■ Results and Discussionmentioning

confidence: 99%

Bromination and Accompanying Rearrangement of the Polycyclic Oxetane 2,4-Oxytwistane

et al. 2014

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Bromination of the polycyclic oxetane 2,4-oxytwistane (rac-(1R,3S,4R,7S,9R,11S)-2-oxatetracyclo[5.3.1.0(3,11).0(4,9)]undecane) was undertaken in order to form 2,4-dibromotwistane. The oxetane was subjected to the mild reagent combination CBr4/Ph3P in a fashion similar to that for the Appel and Corey-Fuchs reactions. NMR spectroscopy revealed that the isomeric dibromo compound 2,8-dibromoisotwistane (2,8-dibromotricyclo[4.3.1.0(3,7)]decane) was inadvertently formed. The conversion was prevented by migration of a C-C bond within the geometrically stressed C10 framework. Computational chemistry was used to model the structure of the polycyclic oxetane and to assess the component of total ring strain energy due to the four-membered heterocycle. Mechanistic aspects behind the skeletal rearrangement are also discussed.

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“…Este método permite obter o brometo em rendimento quantitativo 23 . Dentre os diversos métodos relatados na literatura para preparar a 2,4-tiazolidinadiona 1, foi empregado o método descrito por Libermann et al 20 , por apresentar bom rendimento.…”

Section: Resultsunclassified

Síntese e atividade antiedematogênica de derivados N-triptofil-5-benzilideno-2,4-tiazolidinadiona e N-triptofil-5-benzilideno-rodanina

Góes¹,

Lima²,

Nagy³

et al. 2004

Quím. Nova

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, 50670-901 Recife -PE Recebido em 13/11/03; aceito em 22/6/04; publicado na web em 8/10/04 SYNTHESIS AND ANTIEDEMATOGENIC ACTIVITY OF SOME N-TRYPTHOPHYL-5-BENZYLIDENE-2,4-THIAZOLIDINEDIONE AND N-TRYPTHOPHYL-5-BENZYLIDENE-RHODANINE DERIVATIVES. Derivatives of Ntryptophyl-5-benzylidene-2,4-thiazolidinedione (7a-c) and N-tryptophyl-5-benzylidene-rhodanine (7d-f) were prepared by condensation of the intermediates 5 and 6 with different benzaldehydes, respectively. Their structural elucidation was carried through by IR, 1 H NMR and MS. The acute toxicity and antiedematogenic activity of the compounds 7b,c and 7e,f were evaluated. The data did not reveal any sign of toxicity, and no mortality was registered. As indomethacin (10 mg/kg; v.o.), the antiedematogenic activity of the compounds 7b (50 mg/kg; v.o.) and 7e, 7f (50 or 100 mg/kg; v.o.) against carrageenan-induced paw edema was verified at time intervals of 180 min.

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Direct conversion of tetrahydropyranylated alcohols to the corresponding bromides

Cited by 61 publications

References 6 publications

Phosphonate analogues of cyclopropavir phosphates and their E-isomers. Synthesis and antiviral activity

Phosphonate analogues of cyclopropavir phosphates and their E-isomers. Synthesis and antiviral activity

Bromination and Accompanying Rearrangement of the Polycyclic Oxetane 2,4-Oxytwistane

Síntese e atividade antiedematogênica de derivados N-triptofil-5-benzilideno-2,4-tiazolidinadiona e N-triptofil-5-benzilideno-rodanina

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