Impairment of prostate cancer cell growth by a selective and reversible lysine-specific demethylase 1 inhibitor.

Post-translational modifications of histones by chromatin modifying enzymes regulate chromatin structure and gene expression. As deregulation of histone modifications contributes to cancer progression, inhibition of chromatin modifying enzymes such as histone demethylases is an attractive therapeutic strategy to impair cancer growth. Lysine-specific demethylase 1 (LSD1) removes mono- and dimethyl marks from lysine 4 or 9 of histone H3. LSD1 in association with the androgen receptor (AR) controls androgen-dependent gene expression and prostate tumor cell proliferation, thus highlighting LSD1 as a drug target. By combining protein structure similarity clustering and in vitro screening, we identified Namoline, a γ-pyrone, as a novel, selective and reversible LSD1 inhibitor. Namoline blocks LSD1 demethylase activity in vitro and in vivo. Inhibition of LSD1 by Namoline leads to silencing of AR-regulated gene expression and severely impairs androgen-dependent proliferation in vitro and in vivo. Thus, Namoline is a novel promising starting compound for the development of therapeutics to treat androgen-dependent prostate cancer.

Principles, implementation, and application of biology-oriented synthesis (BIOS).

Biology-oriented synthesis (BIOS) represents an alternative approach for the generation of compound collections for biological applications. In BIOS, biologically relevant and prevalidated scaffold structures, such as core structures of natural products or known drugs, are employed as scaffolds for the generation of compound collections with focused diversity. In this review, we discuss the underlying concept of the BIOS approach, and its practical implementation in library design and synthesis. To highlight its relevance for chemical biology applications, we finally present examples in which compound collections generated under the BIOS principle have been used to elucidate biological questions.

Biology-oriented combined solid- and solution-phase synthesis of a macroline-like compound collection.

Macrolines constitute a class of natural products that has more than 100 members and displays diverse biological activities. These compounds feature a cycloocta[b]indole scaffold that represents an interesting target structure for biology-oriented synthesis (BIOS). We have presented a solid-phase synthesis of isomerically pure cycloocta[b]indoles by employing the Pictet-Spengler reaction and the Dieckmann cyclization as key steps. The scope of this reaction sequence was investigated in more detail by using various additional diversification procedures, such as Pd-catalyzed Sonogashira or Suzuki couplings on a solid phase, thus allowing, for example, the generation of 10-substituted cycloocta[b]indole derivatives. Finally, solution-phase decoration of the cycloocta[b]indole skeleton by reduction and saponification was evaluated, thereby further extending the scope of the solid-phase synthesis.

Gamma-pyrone natural products--a privileged compound class provided by nature.

In "Biology Oriented Synthesis" (BIOS), the inherent biological relevance of natural products is employed for the design and synthesis of compound libraries. Towards this end, library generation in BIOS is focused on compound classes from biologically relevant space such as the natural product space or also the drug space and only scaffolds of these areas of proven relevance are employed for synthesis of small focused libraries with limited diversity. We here present a short overview of gamma-pyrone natural products, highlighting their biological properties and their potential applicability in a BIOS of a compound library.

Synthesis and unexpected reactivity of Si-H functionalized dithieno[3,2-b:2',3'-d]phospholes.

[reaction: see text]. Si-H functionalized, blue light-emitting dithieno[3,2-b:2',3'-d]phospholes are accessible by reaction of an appropriate bithiophene precursor with a dichlorophosphane. Subsequent functionalization of the central phosphorus center allows for a fine-tuning of the optoelectronic properties of the material. Pt-catalyzed reaction of the Si-H functionalities with alkynes affords the hydrosilation products including a polymer by reaction with 1,7-octadiyne. By contrast, the absence of any substrate leads to the exclusive formation of a polymer via dehydrogenative homocoupling.