- Synthesis and antibacterial activity of 9-substituted minocycline derivatives
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A number of 9-acylamino and 9-sulfonylamino derivatives of minocycline have been synthesized for structure-activity relationship studies. These compounds showed activity against both tetracycline-susceptible and tetracycline-resistant strains. Many of the
- Sum, Phaik-Eng,Ross, Adma T.,Petersen, Peter J.,Testa, Raymond T.
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- Minocycline-based europium(III) chelate complexes: Synthesis, luminescent properties, and labeling to streptavidin
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Two chelate ligands for europium(III) having minocycline (=(4S,4aS,5aR,12aS)-4,7-bis(dimethylamino)-1,4,4a,5,5a,6,11,12a-octahydro-3,10, 12,12a-tetrahydroxy-1,11-dioxonaphthacene-2-carboxamide; 5) as a VIS-light-absorbing group were synthesized as possible VIS-light-excitable stable Eu3+ complexes for protein labeling. The 9-amino derivative 7 of minocycline was treated with H6TTHA (= triethylenetetraminehexaacetic acid=3,6,9,12-tetrakis(carboxymethyl)-3,6,9,12- tetraazatetradecanedioic acid) or H5DTPA (= diethylenetriaminepentaacetic acid=N,N-bis{2-[bis(carboxymethyl)amino]ethyl} glycine) to link the polycarboxylic acids to minocycline. One of the Eu 3+ chelates, [Eu3+(minocycline-TTHA)] (13), is moderately luminescent in H2O by excitation at 395 nm, whereas [Eu 3+(minocycline-DTPA)] (9) was not luminescent by excitation at the same wavelength. The luminescence and the excitation spectra of [Eu 3+(minocycline-TTHA)] (13) showed that, different from other luminescent EuIII chelate complexes, the emission at 615 nm is caused via direct excitation of the Eu3+ ion, and the chelate ligand is not involved in the excitation of Eu3+. However, the ligand seems to act for the prevention of quenching of the Eu3+ emission by H2O. The fact that the excitation spectrum of [Eu3+(minocycline-TTHA)] is almost identical with the absorption spectrum of Eu3+ aqua ion supports such an excitation mechanism. The high stability of the complexes of [Eu3+(minocycline-DTPA)] (9) and [Eu3+(minocycline-TTHA)] (13) was confirmed by UV-absorption semi-quantitative titrations of H 4(minocycline-DTPA) (8) and H5(minocycline-TTHA) (12) with Eu 3+. The titrations suggested also that an 1:1 ligand Eu3+ complex is formed from 12, whereas an 1:2 complex was formed from 8 minocycline-DTPA. The H5(minocycline-TTHA) (12) was successfully conjugated to streptavidin (SA) (Scheme 5), and thus the applicability of the corresponding Eu3+ complex to label a protein was established.
- Nishioka, Takuya,Yamamoto, Yuji,Hashino, Kimikazu,Matsumoto, Kazuko
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- An improved process for the preparation of Tigecycline intermediate and process for the preparation of Tigecycline therefrom
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The present invention relates to a process for the preparation of Tigecycline intermediate i.e. 9-amino minocycline of formula-1(C). More particularly, the present invention relates to a process for the preparation of 9-amino minocycline of formula 1(C) and a process for the preparation of Tigecycline of formula 1 from 9-nitro minocycline of formula 1(B).
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Page/Page column 12-13
(2022/02/15)
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- TIGECYCLINE AND METHODS OF PREPARING INTERMEDIATES
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Methods of preparing and purifying 9-nitrominocycline and 9-aminominocycline and salts thereof used in the process of making tigecycline, are disclosed. In one embodiment, the invention is directed to a method of preparing the compound of formula 1 or a pharmaceutically acceptable salt thereof, comprising: (a) reacting nitric acid with the compound of formula 2, or a salt thereof, to produce a reaction mixture comprising an intermediate; and (b) further reacting the intermediate to form the compound of formula 1, wherein the intermediate is isolated from the reaction mixture, the method further comprising sparging with an inert gas prior to step (a).
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Page/Page column 11-12; 13-14
(2009/04/24)
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- Isolation of tetracycline derivatives
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Provided is a process for the isolation of tetracycline derivatives.
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Page/Page column 2-3
(2008/06/13)
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