Synthesis of Analogs of D-Ala--D-Ala as Potential Inhibitors of Bacterial Cell Wall Biosynthesis.
摘要:
The syntheses of the L,L- and D,D-stereoisomers of N- phenoxyacetyl -X-alanine in which X = Ser, Ala( beta Cl ) or Arg, are described. The antibacterial activity of these peptides and some of their synthetic intermediates has been examined. Four of the intermediates in which X = Ala( beta Cl ) and Arg(NO2), which possess C-terminal benzyl ester groups, were active against viridans streptococci and Streptococcus agalactiae. The D,D-enantiomers were more active than the corresponding L,L-isomers. None of the compounds were active against beta-lactamase producing bacteria or acted as beta-lactamase inhibitors.
In this study, several novelβ-carbolinederivatives, 1-(4-hydroxy-3-methoxyphenyl)-β-carboline-3-carboxyl-Trp-Trp-AA-OBzl compounds, were designed and synthesized as potential anticancer agents. Their in vitro cytotoxic activities were evaluated using methylthiazoltetrazolium (MTT) assay. The in vivo anti-tumor activity of the newly synthesized β-carbolinederivatives was determined in a S180 bearing
Benzoxazinyl-amidocyclopentyl-heterocyclic modulators of chemokine receptors
申请人:Goble D. Stephen
公开号:US20070238723A1
公开(公告)日:2007-10-11
Cyclopentyl compounds linked to a benzoxazinyl group through an amido moiety utilizing the ring nitrogen of the benzoxazine, and further substituted with a heterocyclic moiety, such compounds represented by formula I:
which are used to modulate the CCR-2 chemokine receptor to prevent or treat inflammatory and immunoregulatory disorders and diseases, allergic diseases, atopic conditions including allergic rhinitis, dermatitis, conjunctivitis, and asthma, as well as autoimmune pathologies such as rheumatoid arthritis and atherosclerosis; and pharmaceutical compositions comprising these compounds and the use of these compounds and compositions.
The present invention provides novel N-substituted fluorooxindoles having the general Formula I
wherein the wavy bond
represents the racemate, the (R)-enantiomer or the (S)-enantiomer and m, n, p, q, A, B, D, Q, X, and Z are as defined below, or a nontoxic pharmaceutically acceptable salt or solvate thereof and are useful in the treatment of disorders which are responsive to the opening of potassium channels.
Stereochemical Elucidation and Total Synthesis of Dihydropacidamycin D, a Semisynthetic Pacidamycin
作者:Constantine G. Boojamra、Rémy C. Lemoine、Julie C. Lee、Roger Léger、Karin A. Stein、Nicole G. Vernier、Angela Magon、Olga Lomovskaya、Patrick K. Martin、Suzanne Chamberland、May D. Lee、Scott J. Hecker、Ving J. Lee
DOI:10.1021/ja003292c
日期:2001.2.1
that of the natural products. Elucidation of stereochemistry in the pacidamycins has been completed through a campaign of natural product degradation experiments in combination with the totalsynthesis of the lowest-molecular weight dihydropacidamycin, dihydropacidamycin D. The stereochemical identities of the tryptophan and two alanine residues contained in pacidamycin D have been shown to be of the
已显示太平洋霉素的 C(4') 环外烯烃的氢化作用产生一系列半合成化合物,即二氢太平洋霉素,其抗菌活性类似于天然产物。通过天然产物降解实验以及最低分子量二氢太平洋霉素 D 的全合成,已经完成了太平洋霉素中立体化学的阐明。 太平洋霉素 D 中包含的色氨酸和两个丙氨酸残基的立体化学身份已经确定显示为天然 (S) 构型,而该系列抗生素中所含的独特 3-甲基氨基-2-氨基丁酸已显示为 (2S,3S) 构型。最后,通过氢化 C(4')-C(5'
Synthesis and In Vitro Antibacterial Activity of Catechol-spiramycin Conjugates.
The first synthesis of siderophore conjugates of two macrolide antibiotics, spiramycin 1 and neospiramycin 2, which are unable to penetrate the outer membrane of Gramnegative bacteria are described. These novel conjugates were prepared by regioselective acylation of a hydroxyl function of 1 and 2 with a dihydroxybenzoic Fe(III) complexing ligand linked via a carboxyl group containing spacer to the macrolide antibiotics. The preliminary biological evaluation of these novel conjugates under standard and iron depleted conditions has shown that their antibacterial activity was comparable to that of spiramycin 1 and neospiramycin 2.