Iron-Catalyzed Synthesis of Sulfur-Containing Heterocycles.

An iron-catalyzed synthesis of sulfur- and sulfone-containing heterocycles is reported. The method is based on the cyclization of readily available substrates and proceeded with high efficiency and diastereoselectivity. A variety of sulfur-containing heterocycles bearing moieties suitable for subsequent functionalization are prepared. Illustrative examples of such postcyclization modifications are also presented.

Tankyrase inhibition impairs directional migration and invasion of lung cancer cells by affecting microtubule dynamics and polarity signals.

BACKGROUND: Tankyrases are poly(adenosine diphosphate)-ribose polymerases that contribute to biological processes as diverse as modulation of Wnt signaling, telomere maintenance, vesicle trafficking, and microtubule-dependent spindle pole assembly during mitosis. At interphase, polarized reshaping of the microtubule network fosters oriented cell migration. This is attained by association of adenomatous polyposis coli with the plus end of microtubules at the cortex of cell membrane protrusions and microtubule-based centrosome reorientation towards the migrating front. RESULTS: Here we report a new function for tankyrases, namely, regulation of directional cell locomotion. Using a panel of lung cancer cell lines as a model system, we found that abrogation of tankyrase activity by two different, structurally unrelated small-molecule inhibitors (one introduced and characterized here for the first time) or by RNA interference-based genetic silencing weakened cell migration, invasion, and directional movement induced by the motogenic cytokine hepatocyte growth factor. Mechanistically, the anti-invasive outcome of tankyrase inhibition could be ascribed to sequential deterioration of the distinct events that govern cell directional sensing. In particular, tankyrase blockade negatively impacted (1) microtubule dynamic instability; (2) adenomatous polyposis coli plasma membrane targeting; and (3) centrosome reorientation. CONCLUSIONS: Collectively, these findings uncover an unanticipated role for tankyrases in influencing at multiple levels the interphase dynamics of the microtubule network and the subcellular distribution of related polarity signals. These results encourage the further exploration of tankyrase inhibitors as therapeutic tools to oppose dissemination and metastasis of cancer cells.

Access to Silylated Pyrazole Derivatives by Palladium-Catalyzed C-H Activation of a TMS group.

A simple and efficient approach to new silylated heterocycles of potential interest in medicinal chemistry is presented. A set of bromophenyl trimethylsilyl pyrazole intermediates can be transformed by direct organometallic routes into two families of regioisomeric iodoaryl substrates; using either arylzinc or aryllithium chemistry, the TMS group remains on the pyrazole ring or translocates to the aryl moiety. These two families can then be efficiently transformed into benzo silino pyrazoles thanks to a single-step cyclization relying on the Pd-catalyzed activation of a non-activated C(sp(3) )-H bond alpha to a silicon atom. The experimental conditions used, which are fully compatible with the pyrazole ring, suggest that this reaction evolves through a concerted metalation-deprotonation (CMD) mechanism.

Iron-Catalyzed Synthesis of C2 Aryl- and N-Heteroaryl-Substituted Tetrahydropyrans.

An iron-catalyzed cyclization of hydroxy allylic derivatives into tetrahydropyrans possessing an N-heteroaryl at C2 is disclosed. The reaction proceeds with good yield and in high diastereoselectivity in favor of the more stable isomer. The diastereoselectivity results from an iron-induced reopening of the tetrahydropyrans, allowing a thermodynamic equilibration. The method allows access to a variety of 2,6-disubstituted as well as 2,4,6-trisubstituted tetrahydropyrans that could be considered as attractive scaffolds for the pharmaceutical industry.

Anionic access to silylated and germylated binuclear heterocycles.

A simple access to silylated and germylated binuclear heterocycles, based on an original anionic rearrangement, is described. A set of electron-rich and electron-poor silylated aromatic and heteroaromatic substrates were tested to understand the mechanism and the factors controlling this rearrangement, in particular its regioselectivity. This parameter was shown to follow the rules proposed before from a few examples. Then, the effect of the substituents borne by the silicon itself, in particular the selectivity of the ligand transfer, was studied. Additionally, this chemistry was extended to germylated substrates. A hypervalent germanium species, comparable to the putative intermediate proposed with silicon, seems to be involved. However, a pathway implicating the elimination of LiCH2Cl was observed for the first time with this element, leading to unexpected products of the benzo-oxa (or benzo-aza) germol-type.

Synthesis of substituted indenones and indanones by a Suzuki-Miyaura coupling/acid-promoted cyclisation sequence.

A one-pot Suzuki-Miyaura cross-coupling/acid-catalyzed cyclisation leading to indenones and indanones in modest to good yields is reported.

Cobalt-catalyzed diastereoselective synthesis of C-furanosides. Total synthesis of (-)-isoaltholactone.

An array of C-aryl and C-vinyl furanosides were prepared in good yields and diastereoselectivities from C-halogeno furanosides either with aryl Grignard or with vinyl Grignard using the convenient Co(acac)3/TMEDA catalytic system. This method is illustrated by the total synthesis of the (-)-isoaltholactone.

Diastereoselective metal-catalyzed synthesis of C-aryl and C-vinyl glycosides.

Cobalt, the catalyst of choice: The diastereoselective cobalt-catalyzed cross-coupling of 1-bromo glycosides and aryl or vinyl Grignard reagents is described. A convenient and inexpensive catalyst, [Co(acac)(3)]/tmeda (acac = acetylacetonate, tmeda = N,N'-tetramethylethylenediamine), gives full α selectivity in the mannose and galactose series, and an α selectivity in the glucose series with α/ß ratios of 1.3:1-3:1.

Identification of a series of substituted 2-piperazinyl-5-pyrimidylhydroxamic acids as potent histone deacetylase inhibitors.

Pursuing our efforts in designing 5-pyrimidylhydroxamic acid anti-cancer agents, we have identified a new series of potent histone deacetylase (HDAC) inhibitors. These compounds exhibit enzymatic HDAC inhibiting properties with IC(50) values in the nanomolar range and inhibit tumor cell proliferation at similar levels. Good solubility, moderate bioavailability, and promising in vivo activity in xenograft model made this series of compounds interesting starting points to design new potent HDAC inhibitors.

Impact on farnesyltransferase inhibition of 4-chlorophenyl moiety replacement in the Zarnestra series.

Based on the structure of R115777 (tipifarnib, Zarnestra), a series of farnesyltransferase inhibitors have been synthesized by modification of the 2-quinolinone motif and transposition of the 4-chlorophenyl ring to the imidazole or its replacement by 5-membered rings. This has yielded a novel series of potent farnesyltransferase inhibitors.

Discovery and Pharmacological Characterization of JNJ-42756493 (Erdafitinib), a Functionally Selective Small-Molecule FGFR Family Inhibitor.

Fibroblast growth factor (FGF) signaling plays critical roles in key biological processes ranging from embryogenesis to wound healing and has strong links to several hallmarks of cancer. Genetic alterations in FGF receptor (FGFR) family members are associated with increased tumor growth, metastasis, angiogenesis, and decreased survival. JNJ-42756493, erdafitinib, is an orally active small molecule with potent tyrosine kinase inhibitory activity against all four FGFR family members and selectivity versus other highly related kinases. JNJ-42756493 shows rapid uptake into the lysosomal compartment of cells in culture, which is associated with prolonged inhibition of FGFR signaling, possibly due to sustained release of the inhibitor. In xenografts from human tumor cell lines or patient-derived tumor tissue with activating FGFR alterations, JNJ-42756493 administration results in potent and dose-dependent antitumor activity accompanied by pharmacodynamic modulation of phospho-FGFR and phospho-ERK in tumors. The results of the current study provide a strong rationale for the clinical investigation of JNJ-42756493 in patients with tumors harboring FGFR pathway alterations. Mol Cancer Ther; 16(6); 1010-20. ©2017 AACR.

Discovery of pyrimidyl-5-hydroxamic acids as new potent histone deacetylase inhibitors.

A series of pyrimidyl-5-hydroxamic acids was prepared for evaluation as inhibitors of histone deacetylase (HDAC). Amino-2-pyrimidinyl can be used as a linker to provide HDAC inhibitors of good enzymatic potency.

Farnesyl protein transferase inhibitor ZARNESTRA R115777 - history of a discovery.

R115777 (R)-6-amino[(4-chlorophenyl)(1-methyl-1H-imidazol-5-yl)methyl]-4-(3-chlorophenyl)-1-methyl-2(1H)-quinolinone is a potent and selective inhibitor of farnesyl protein transferase with significant antitumor effects in vivo subsequent to oral administration in mice. Taking its roots into Janssen's ketoconazole and retinoic acid catabolism programs, our interest into Ras prenylation process led us stepwise to identify the key structural features of R115777. Methodology, structure activity relationships, and pharmacology will be presented. R115777 is currently in phase III clinical evaluation.

Tandem Suzuki-Miyaura coupling/acid-catalyzed cyclization between vinyl ether boronates and vinyl halides: a concise approach to polysubstituted furans.

Polysubstituted 2-(ω-hydroxyalkyl)furans were prepared by tandem Suzuki-Miyaura coupling/acid-catalyzed cyclization starting from appropriately substituted 3-haloallylic alcohols and dihydrofuran-, dihydropyran- or glycal-derived pinacol boronates.

Intramolecular sila-Matteson rearrangement: a general access to silylated heterocycles.

A series of new silylated heterocycles has been efficiently prepared using an intramolecular silicon version of the Matteson rearrangement, providing two isomers of binuclear heterocycles. This method applies to a large variety of substrates, a direct relationship between the Hammett constants of the aromatic substituents and the isomer ratio being observed. Complementary experiments suggest that a common pentaorganosilicate species is involved.

Two-step one-pot synthesis of benzoannulated spiroacetals by Suzuki-Miyaura coupling/acid-catalyzed spiroacetalization.

Substituted benzoannulated spiroacetals were prepared from (2-haloaryl)alkyl alcohols and dihydropyranyl or dihydrofuranyl pinacol boronates using a Suzuki-Miyaura coupling followed by an acid-catalyzed spirocyclization. Application of the reaction to a glycal boronate provides an approach to annulated spiroacetals in enantiopure form.

Potent, selective inhibitors of fibroblast growth factor receptor define fibroblast growth factor dependence in preclinical cancer models.

We describe here the identification and characterization of 2 novel inhibitors of the fibroblast growth factor receptor (FGFR) family of receptor tyrosine kinases. The compounds exhibit selective inhibition of FGFR over the closely related VEGFR2 receptor in cell lines and in vivo. The pharmacologic profile of these inhibitors was defined using a panel of human tumor cell lines characterized for specific mutations, amplifications, or translocations known to activate one of the four FGFR receptor isoforms. This pharmacology defines a profile for inhibitors that are likely to be of use in clinical settings in disease types where FGFR is shown to play an important role.

JNJ-26481585, a novel "second-generation" oral histone deacetylase inhibitor, shows broad-spectrum preclinical antitumoral activity.

PURPOSE: Histone deacetylase (HDAC) inhibitors have shown promising clinical activity in the treatment of hematologic malignancies, but their activity in solid tumor indications has been limited. Most HDAC inhibitors in clinical development only transiently induce histone acetylation in tumor tissue. Here, we sought to identify a "second-generation" class I HDAC inhibitor with prolonged pharmacodynamic response in vivo, to assess whether this results in superior antitumoral efficacy. EXPERIMENTAL DESIGN: To identify novel HDAC inhibitors with superior pharmacodynamic properties, we developed a preclinical in vivo tumor model, in which tumor cells have been engineered to express fluorescent protein dependent on HDAC1 inhibition, thereby allowing noninvasive real-time evaluation of the tumor response to HDAC inhibitors. RESULTS: In vivo pharmacodynamic analysis of 140 potent pyrimidyl-hydroxamic acid analogues resulted in the identification of JNJ-26481585. Once daily oral administration of JNJ-26481585 induced continuous histone H3 acetylation. The prolonged pharmacodynamic response translated into complete tumor growth inhibition in Ras mutant HCT116 colon carcinoma xenografts, whereas 5-fluorouracil was less active. JNJ-26481585 also fully inhibited the growth of C170HM2 colorectal liver metastases, whereas again 5-fluorouracil/Leucovorin showed modest activity. Further characterization revealed that JNJ-26481585 is a pan-HDAC inhibitor with marked potency toward HDAC1 (IC(50), 0.16 nmol/L). CONCLUSIONS: The potent antitumor activity as a single agent in preclinical models combined with its favorable pharmacodynamic profile makes JNJ-26481585 a promising "second-generation" HDAC inhibitor. The compound is currently in clinical studies, to evaluate its potential applicability in a broad spectrum of both solid and hematologic malignancies.

4-methyl-1,2,4-triazol-3-yl heterocycle as an alternative to the 1-methylimidazol-5-yl moiety in the farnesyltransferase inhibitor ZARNESTRA.

Replacement of the 1-methylimidazol-5-yl moiety in the farnesyltransferase inhibitor ZARNESTRA series by a 4-methyl-1,2,4-triazol-3-yl group gave us compounds with similar structure-activity relationship profiles showing that this triazole is potentially a good surrogate to imidazole for farnesyltransferase inhibition.

5-imidazolyl-quinolinones, -quinazolinones and -benzo-azepinones as farnesyltransferase inhibitors.

The evaluation of structure-activity relationships associated with the modification of the R115777 quinolinone ring moiety displaying potent in vitro inhibiting activity is described.