Synthesis, in vitro antiproliferative activities, and Chk1 inhibitory properties of dipyrrolo[3,4-a:3,4-c]carbazole-triones

Synthesis of Polycyclic Tetrahydroisoquinolines and Tetrahydrobenzo[d]azepines from Polymer-Supported Allylglycine

Herein, we report a multistep synthesis of polycyclic tetrahydroisoquinolines and tetrahydrobenzo[d]azepines starting from Wang resin-immobilized allylglycine. After sulfonylation with 2/4-nitrobenzenesulfonyl chlorides, Mitsunobu alkylation with various phenylalkynols yielded the corresponding (phenylprop-2-yn-1-yl)-sulfonamides. "Interior" ring-closure enyne metathesis (RCEM) using a Grubbs catalyst second generation (Ru2) yielded functionalized tetrahydroisoquinoline/tetrahydrobenzo[d]azepine intermediates. "East-side" [4 + 2] cycloaddition with representative dienophiles was followed by the "west-side" construction of different heterocycles using various electrophiles to finally furnish a set of novel molecular frameworks bearing fused [6 + 6] or [6 + 7] rings. The developed methodology enables the facile parallel synthesis of novel, pharmacologically promising compounds derived from privileged scaffolds.

Carbazole Derivatives as Kinase-Targeting Inhibitors for Cancer Treatment

Protein Kinases (PKs) are a heterogeneous family of enzymes that modulate several biological pathways, including cell division, cytoskeletal rearrangement, differentiation and apoptosis. In particular, due to their crucial role during human tumorigenesis and cancer progression, PKs are ideal targets for the design and development of effective and low toxic chemotherapeutics and represent the second group of drug targets after G-protein-coupled receptors. Nowadays, several compounds have been claimed to be PKs inhibitors, and some of them, such as imatinib, erlotinib and gefitinib, have already been approved for clinical use, whereas more than 30 others are in various phases of clinical trials. Among them, some natural or synthetic carbazole-based molecules represent promising PKs inhibitors due to their capability to interfere with PK activity by different mechanisms of action including the ability to act as DNA intercalating agents, interfere with the activity of enzymes involved in DNA duplication, such as topoisomerases and telomerases, and inhibit other proteins such as cyclindependent kinases or antagonize estrogen receptors. Thus, carbazoles can be considered a promising this class of compounds to be adopted in targeted therapy of different types of cancer.

Diastereoselective synthesis of functionalised carbazoles via a sequential Diels–Alder/ene reaction strategy

A one-pot, three-component, synthesis of saturated carbazoles and related pyridazino[3,4-b]indoles is described, involving an intermolecular Diels–Alder/intermolecular ene reaction sequence with relative stereocontrol of up to four stereocentres.

3,6-Di-chloro-9-(prop-2-yn-1-yl)-9H-carbazole

The tricyclic aromatic ring system of the title compound, C₁₅H₉Cl₂N, is essentially planar (r.m.s. deviation = 0.002 Å). The two Cl atoms lie slightly out of the plane of the carbazole ring system, with the C—Cl bonds forming angles of 1.23 (8) and 1.14 (8)° with the plane. The acetylene group has a syn orientation with respect to the ring system. In the crystal, no weak hydrogen bonds nor any π–π stacking inter­actions are observed.

Synthesis, checkpoint kinase 1 inhibitory properties and in vitro antiproliferative activities of new pyrrolocarbazoles

In the course of structure-activity relationship studies on granulatimide analogues, new pyrrolo[3,4-c]carbazoles have been synthesized in which the imidazole heterocycle was replaced by a five-membered ring lactam system or a dimethylcyclopentanedione. Moreover, the synthesis of an original structure in which a sugar moiety is attached to the indole nitrogen and to a six-membered D ring via an oxygen is reported. The inhibitory activities of the newly synthesized compounds toward checkpoint kinase 1 and their in vitro antiproliferative activities toward three tumor cell lines: murine leukemia L1210, and human colon carcinoma HT29 and HCT116 are described.

Synthesis, in vitro antiproliferative activities, and Chk1 inhibitory properties of pyrrolo[3,4-a]carbazole-1,3-diones, pyrrolo[3,4-c]carbazole-1,3-diones, and 2-aminopyridazino[3,4-a]pyrrolo[3,4-c]carbazole-1,3,4,7-tetraone

The synthesis of substituted pyrrolo[3,4-a]carbazole-1,3-diones, pyrrolo[3,4-c]carbazole-1,3-diones, and 2-aminopyridazino[3,4-a]pyrrolo[3,4-c]carbazole-1,3,4,7-tetraone is reported. Their inhibitory properties toward Checkpoint 1 kinase (Chk1) have been evaluated and their in vitro antiproliferative activities toward three tumor cell lines: murine leukemia L1210, human colon carcinoma HT29 and HCT116 have been determined. From the biological results, it appears that, in contrast with the upper E heterocycle, the lower D heterocycle is not absolutely required for Chk1 inhibition. The ATP binding pocket of Chk1 seems to be adaptable to substitution of the nitrogen of the imide E heterocycle with a hydroxymethyl group, allowing the fundamental hydrogen bond with the Glu(85) residue of the enzyme.