ChemInform Abstract: Antifungal Quinazolinones from Marine-Derived Bacillus cereus and Their Preparation.

Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, People's Republic of China.
Bioorganic & medicinal chemistry letters (Impact Factor: 2.33). 07/2011; 21(13):4005-7. DOI: 10.1016/j.bmcl.2011.05.002
Source: PubMed

ABSTRACT Two new quinazolinones alkaloids, R(+)-2-(heptan-3-yl)quinazolin-4(3H)-one (1) and (2R,3'R)+(2S,3'R)-2-(heptan-3-yl)-2,3-dihydroquinazolin-4(1H)-one (2) (a pair of epimers), as well as seven known analogues, 2-methylquinazolin-4(3H)-one (3), 2-benzylquinazolin-4(3H)-one (4), cyclo-(Pro-Ile), cyclo-(Pro-Leu), cyclo-(Pro-Val), cyclo-(Pro-Phe), and cyclo-(Tyr-Pro) were isolated from the n-butyl alcohol extract of the marine-derived bacterium Bacillus cereus 041381. The new compounds were identified by spectroscopic analysis and chemical synthesis. Four optical isomers 5-8 were also synthesized. Compounds 1-8 all showed moderate antifungal activity against Candida albicans with MIC values of 1.3-15.6 μM. Compound 5 exhibits the most powerful antifungal activity, which may reveal that S-configuration and 2,3-double bond were necessary for antifungal activity, and the racemization at C-2 and C-3' reduced the antifungal activity.

  • [Show abstract] [Hide abstract]
    ABSTRACT: Novel thiazole, pyrimidine and benzylidene derivatives derived from quinazoline scaffold have been synthesized. The antitumor evaluation of the newly synthesized products against three cancer cell lines namely breast adenocarcinoma (MCF-7), non-small cell lung cancer (NCI-H460), and CNS cancer (SF-268) showed that the benzylidene–quinazoline derivative 12a showed remarkable activity against all three cell lines. The thiazolo-quinazoline derivative 10 showed greater activity than the control against breast adenocarcinoma (MCF-7) with a concentration of 0.01 μM. Moreover, the antileishmanial activity of the newly synthesized products tested on Leishmania donovani amastigotes showed that compounds 4, 14, and 18 had very promising activity.
    Medicinal Chemistry Research 05/2012; 22(5). DOI:10.1007/s00044-012-0213-9 · 1.61 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Diketopiperazines (DKPs) are a class of secondary metabolites that result from peptide bonds between two amino acids to form a lactam. Due to their rigid structure, chiral nature, and varied side chains, DKPs have been of research interest for their diverse bioactivities. However, little is known about whether DPKs stimulate the release of cytokine and chemokines in macrophage cells. The present aim was to study the effect of DKPs firstly isolated from sponge Callyspongia sp. on the release of several cytokines in murine macrophage-like cell line J774A.1 after stimulation in vitro, and their potential structure-activity relationship of five natural DKPs on four representative cytokines, interferon-γ (IFN-γ), pro-inflammatory (tumor necrosis factor, TNF-α), anti-inflammatory cytokine (interleukin-10, IL-10), and chemokine (monocyte chemoattractant protein-1, MCP-1). Results suggested that these five DKPs, especially DKP 1 bearing 3-hydroxyl-l-proline (l-Hyp), might be useful as a promising macrophage cytokines stimulator.
    Bioorganic & medicinal chemistry letters 03/2012; 22(9):3177-80. DOI:10.1016/j.bmcl.2012.03.045 · 2.33 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Enantioselective synthesis of 2,3-dihydroquinazolinones (DHQZs) was accomplished using readily available Sc(III)-inda-pybox as the catalyst. This is the first report on the metal catalyzed asymmetric intramolecular amidation of imines to synthesize DHQZs.
    Organic Letters 04/2012; 14(7):1896-9. DOI:10.1021/ol300518m · 6.32 Impact Factor