Methanol Derivatives Research Articles

Abstract 2686: Polyphenolic triptorelin and leuprorelin derivatives as anticancer prodrugs

Abstract Triptorelin (TRP) and Leuprorelin (LEP) are two synthetic analogue of gonadotropin-releasing hormone (GnRH), first was approved by the FDA for treatment of advanced prostate cancer and endometriosis in mid 80s. The surge of testosterone, known as a flare effect, is the major side-effect of cancer chemotherapy using TRP and LEP in a combination regiment. Therefore, improving of the biological activity of TRP and LEP by increasing the cellular uptake and retention is a remedy to this end.In this research, polyphenolic derivatives were linked to TRP and LEP through hydrophobic linkers to enhance and optimize the hydrophobicity of these drugs with the expectation to improve the cellular uptake. In this regard, several TRP and LEP conjugates of tris(4-methoxyphenyl)methanol (TPM) derivatives with optimized hydrophobicity were synthesized by the reaction of methoxy benzenes (e.g. methyl 2-methoxybenzoate, 1,2-dimethoxybenzene, methoxy-2-methylbenzene, methoxy-2-nitrobenzene, chloro-2-methxyenzene, anisole, 2-fluoroanisole or 2-methylanisole and 1,3,5-trioxane, followed by the conjugation with TRP or LEP and decanedioic acid or dodecanedioic acid in the presence of HBTU/DIPEA/DIC in moderate yields.Comparative antiproliferative assays between TPM-TRP conjugates and the corresponding non-covalent physical mixtures of the TPM derivatives and TRP were performed against human acute lymphoblastic leukemia (CCRF-CEM), human ovarian adenocarcinoma (SK-OV-3), and mouse pre adipocytes (3T3-L1) cells. TPM-TRP conjugates inhibited the cell proliferation of CCRF-CEM, SK-OV-3 and 3T3-L1 cells by 55-92%, 24-73%, 37-56%, respectively, at a concentration of 10-50 µM after 24-72 h of incubation. Similar antiproliferative assays between TPM-LEP conjugates and the corresponding non-covalent physical mixtures of the TPM derivatives and LEP were performed against human Caucasian prostate adenocarcinoma (PC3), human breast cancer cell line (BT549) and mouse pre-adipocytes (3T3-L1) cells and indicated moderare to high inhibition of the cell proliferation at a concentration of 5-100 µM after 24-72 h of incubation. These data suggest that TPM-TRP and TPM-LEP derivatives with optimized hydrophobicity can be used to improve the biological activity of TRP or LEP. Citation Format: Yousef Beni, Samiyah Alhamed, Jawzah Alnakhli, Kaleh Karim, William Boadi. Polyphenolic triptorelin and leuprorelin derivatives as anticancer prodrugs [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2686.

Copper(II) and zinc(II) as metal-carboxylate coordination complexes based on (1-methyl-1H-benzo[d]imidazol-2-yl) methanol derivative: Synthesis, crystal structure, spectroscopy, DFT calculations and antioxidant activity

This work presents a combined experimental and theoretical study of two new metal-carboxylate coordination compounds. These complexes were prepared from (1-methyl-1H-benzimidazol-2-yl)methanol under mild conditions. The structures of the prepared compounds were characterized by single-crystal X-ray analysis, FTIR and UV–Vis spectroscopy. In the Cupper complex, the Cu(II) ion is coordinated by two ligands, which act as bidentate chelator through the non-substituted N and O atoms, and two carboxylicg oxygen atoms, displaying a hexa-coordinated compound in a distorted octahedral geometry, while in the Zinc complex the ligand is ligated to the Zn(II) ion in monodentate fashion through the N atom, and the metal ion is also bonded to carboxylic oxygen atoms. The tetra-coordinated compound displays a distorted tetrahedral shape. The density functional theory calculations are carried out for the determination of the optimized structures. The electronic transitions and fundamental vibrational wave numbers are calculated and are in good agreement with experimental. In addition, the ligand and its Cu(II) and Zn(II) complexes were screened and evaluated for their potential as DPPH radical scavenger.

Cobalt(II) complexes based on (1-methyl-1H-benzo[d]imidazol-2-yl) methanol derivative: synthesis, crystal structure, spectroscopy, DFT calculations, and antioxidant activity

In this paper, we present a combined experimental and computational study of two new cobalt(II) complexes as [Co(Hmbm)2(OAc)2] and [Co(Hmbm)2(H2O)2]Cl2 (Hmbm = (1-methyl-1H-benzo[d]imidazol-2-yl)methanol). Both complexes were characterized by FT-IR and UV–vis spectroscopy, elemental analysis, and single-crystal X-ray crystallography. The molecular geometries, electronic transitions, and vibrational frequencies of the two complexes and the ligand (Hmbm) in the ground state have been calculated using global hybrid (B3LYP) and range-separated hybrid (CAM-B3LYP) density functional. Qualitative description of excited states and charge transfer character of electronic transitions states were carried out by plotting the Natural Transition Orbitals (NTOs) for main states, and were assigned to LMCT. The ligand and its Co(II) complexes have been evaluated for their potential as DPPH radical scavengers.

Chemoselective synthesis of aryl(pyridinyl)methanol derivatives through Ni-NIXANTPHOS catalyzed α-arylation and tandem arylation/rearrangement of pyridylmethyl ethers

An efficient synthesis of aryl(pyridyl)-methanol derivatives using Ni-NIXANTPHOS catalyzed α-arylation and tandem arylation/rearrangement is described.

Solvent effects on the electrical and magnetic spectroscopic properties of azo-enaminone derivatives in methanol and in water

We have investigated the solvent effects on the nonlinear and spectroscopic optical properties of some azo-enaminone molecules in the gas phase and in methanol and water solutions.

The Direct Catalytic Oxidation of Methane to Methanol-A Critical Assessment.

Despite the large number of disparate approaches for the direct selective partial oxidation of methane, none of them has translated into an industrial process. The oxidation of methane to methanol is a difficult, but intriguing and rewarding, task as it has the potential to eliminate the prevalent natural gas flaring by providing novel routes to its valorization. This Review considers the synthesis of methanol and methanol derivatives from methane by homogeneous and heterogeneous pathways. By establishing the severe limitations related to the direct catalytic synthesis of methanol from methane, we highlight the vastly superior performance of systems which produce methanol derivatives or incorporate specific measures, such as the use of multicomponent catalysts to stabilize methanol. We thereby identify methanol protection as being indispensable for future research on homogeneous and heterogeneous catalysis.

Abstract 2180: Triphenylmethanol conjugates of leuprorelin asanti-cancer prodrugs

Abstract Leuprorelin (LEP) is a synthetic analogue of gonadotropin-releasing hormone (GnRH), first was approved by the FDA for treatment of advanced prostate cancer and endometriosis in 1985. The initial effect of administration LEP is to stimulate the pituitary secretion of FSH and LH. After a prolonged stimulation (constant concentration of LEP in the blood) pituitary becomes insensitive to the action of GnRH. This reduces the level of gonadotropin in the blood, resulting in decreased levels of sex hormones to postcastration or menopausal levels. In addition to the usual side effects of this agonist analogs of LH-RH, other reported adverse effects include transient hypertension, dry mouth, excessive salivation, paraesthesia and increased dysuria. Improving the biological activity of LEP by increasing the cellular uptake and retention is a remedy to this end. In this study, a prodrug strategy has been introduced to optimize the hydrophobicity of LEP by using an appropriate hydrophobic linker attached to tris(4-methoxyphenyl)methanol (TPM) derivatives with the expectation to improve the cellular uptake. In this regard, several LEP conjugates of TPM derivatives with optimized hydrophobicity were synthesized by the reaction of methoxy benzenes (e.g. anisole, 2-fluoroanisole, 2-methylanisole 1,2-dimethoxybenzene or methyl 2-methoxybenzoate and 1,3,5-trioxane, followed by the conjugation with LEP and dodecanedioic acid in the presence of HBTU/DIPEA/DIC in moderate yields. Comparative antiproliferative assays between TPM-LEP conjugates and the corresponding non-covalent physical mixtures of the TPM derivatives and LEP were performed against human Caucasian prostate adenocarcinoma (PC3), human breast cancer cell line (BT549) and mouse pre-adipocytes (3T3-L1) cells and indicated moderare to high inhibition of the cell proliferation at a concentration of 5-100 µM after 24-72 h of incubation. These data suggest that TPM-LEP derivatives with optimized hydrophobicity can be used to improve the biological activity of LEP. Citation Format: Yousef Ahmadibeni, Kaleh Karim, William Boadi. Triphenylmethanol conjugates of leuprorelin asanti-cancer prodrugs [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2180. doi:10.1158/1538-7445.AM2017-2180

Small-Molecule Inhibitors of the Programmed Cell Death-1/Programmed Death-Ligand 1 (PD-1/PD-L1) Interaction via Transiently Induced Protein States and Dimerization of PD-L1.

Blockade of the PD-1/PD-L1 immune checkpoint pathway with monoclonal antibodies has provided significant advances in cancer treatment. The antibody-based immunotherapies carry a number of disadvantages such as the high cost of the antibodies, their limited half-life, and immunogenicity. Development of small-molecule PD-1/PD-L1 inhibitors that could overcome these drawbacks is slow because of the incomplete structural information for this pathway. The first chemical PD-1/PD-L1 inhibitors have been recently disclosed by Bristol-Myers Squibb. Here we present NMR and X-ray characterization for the two classes of these inhibitors. The X-ray structures of the PD-L1/inhibitor complexes reveal one inhibitor molecule located at the center of the PD-L1 homodimer, filling a deep hydrophobic channel-like pocket between two PD-L1 molecules. Derivatives of (2-methyl-3-biphenylyl)methanol exhibit the structures capped on one side of the channel, whereas the compounds based on [3-(2,3-dihydro-1,4-benzodioxin-6-yl)-2-methylphenyl]methanol induce an enlarged interaction interface that results in the open "face-back" tunnel through the PD-L1 dimer.

Innovative analytical method for the determination of underivatized tributyltin and pentachlorophenol in seawater by gas chromatography-triple quadrupole mass spectrometry

Tributyltin (TBT) and pentachlorophenol (PCP) are listed as priority substances that warrant monitoring in the European Water Framework Directive (WFD 2000/60/CE), since TBT and PCP were identified as environmental endocrine disruptors and exhibit considerable toxicity toward both aquatic organisms and mammals even at very low levels.This paper shows a novel approach to analyze underivatized tributyltin (TBT) and pentachlorophenol (PCP) in seawater based on capillary gas chromatography-triple quadrupole mass spectrometry. The optimized extraction method for TBT an PCP in water involved liquid-liquid microextraction with toluene. The reduced extract was added with a solvent mix, composed of methanol and trimethylsilyl derivatives of methanol (MeOTMS), that allowed good chromatographic resolution of underivatized TBT and PCP, interacting as a lubricant along the glass liner during the injection phase.The proposed method showed good linearity and repeatability (RSD%<20% at 0.05 ng L−1 for TBT and 0.2 μg L−1 for PCP). The overall recoveries were 74% and 106% for TBT and PCP, respectively. Very low quantification limits that met the strict statutory and regulatory demands were achieved: 0.002 ng L−1 for TBT and 0.050 μg L−1 for PCP.

Design, synthesis, and antimelanogenic effects of (2-substituted phenyl-1,3-dithiolan-4-yl)methanol derivatives.

The authors designed and synthesized 17 (2-substituted phenyl-1,3-dithiolan-4-yl) methanol (PDTM) derivatives to find a new chemical scaffold, showing excellent tyrosinase-inhibitory activity. Their tyrosinase-inhibitory activities were evaluated against mushroom tyrosinase at 50 μM, and five of the PDTM derivatives (PDTM3, PDTM7–PDTM9, and PDTM13) were found to inhibit mushroom tyrosinase more than kojic acid or arbutin, the positive controls. Of seventeen PDTMs, PDTM3 (half-maximal inhibitory concentration 13.94±1.76 μM), with a 2,4-dihydroxyphenyl moiety, exhibited greatest inhibitory effects (kojic acid half-maximal inhibitory concentration 18.86±2.14 μM). Interestingly, PDTM compounds with no hydroxyl group, PDTM7–PDTM9, also had stronger inhibitory activities than kojic acid. In silico studies of interactions between tyrosinase and the five PDTMs suggested their binding affinities were closely related to their tyrosinase-inhibitory activities. Cell-based experiments performed using B16F10 mouse-skin melanoma cells showed that PDTM3 effectively inhibited melanogenesis and cellular tyrosinase activity. A cell-viability study conducted using B16F10 cells indicated that the antimelanogenic effect of PDTM3 was not attributable to its cytotoxicity. Kinetic studies showed PDTM3 competitively inhibited tyrosinase, indicating binding to the tyrosinase-active site. We found that PDTM3 with a new chemical scaffold could be a promising candidate for skin-whitening agents, and that the 1,3-dithiolane ring could be used as a chemical scaffold for potent tyrosinase inhibition.

Abstract 4807: Triphenylmethanol conjugates of triptorelin as anti-cancer prodrugs

Abstract Triptorelin (TRP) is an anti-cancer agent used for the treatment of a wide variety of hormone-responsive cancers, such as prostate cancer. The surge of testosterone, known as a flare effect, is the major side-effect of cancer chemotherapy using TRP in a combination regiment. Improving the biological activity of TRP by increasing the cellular uptake and retention is a remedy to this end. In this study, the hydrophobicity of TRP was optimized by using an appropriate hydrophobic linker attached to tris(4-methoxyphenyl)methanol (TPM) derivatives with the expectation to improve the cellular uptake. In this regard, a number of TRP conjugates of TPM derivatives with optimized hydrophobicity were synthesized by the reaction of 2-substituted methoxy benzenes (e.g. methyl 2-methoxybenzoate, 1,2-dimethoxybenzene, methoxy-2-methylbenzene, methoxy-2-nitrobenzene, chloro-2-methxyenzene), and 1,3,5-trioxane, followed by the conjugation with TRP and decanedioic acid in the presence of HBTU/DIPEA/DIC in moderate yields. Comparative antiproliferative assays between TPM-TRP conjugates and the corresponding non-covalent physical mixtures of the TPM derivatives and TRP were performed against human acute lymphoblastic leukemia (CCRF-CEM), human ovarian adenocarcinoma (SK-OV-3), and mouse pre adipocytes (3T3-L1) cells. TPM-TRP conjugates inhibited the cell proliferation of CCRF-CEM, SK-OV-3 and 3T3-L1 cells by 55-92%, 24-73%, 37-56%, respectively, at a concentration of 10-50 μM after 24-72 h of incubation. These data suggest that TPM-TRP derivatives with optimized hydrophobicity can be used to improve the biological activity of TRP. Citation Format: Ryan Beni, William Boadi, Jawzah Alnakhli. Triphenylmethanol conjugates of triptorelin as anti-cancer prodrugs. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4807.

Host-Guest Chemistry between Perylene Diimide (PDI) Derivatives and 18-Crown-6: Enhancement in Luminescence Quantum Yield and Electrical Conductivity.

Perylene diimide (PDI) derivatives exhibit a high propensity for aggregation, which causes the aggregation-induced quenching of emission from the system. Host-guest chemistry is one of the best-known methods for preventing aggregation through the encapsulation of guest molecules. Herein we report the use of 18-crown-6 (18-C-6) as a host system to disaggregate suitably substituted PDI derivatives in methanol. 18-C-6 formed complexes with amino-substituted PDIs in methanol, which led to disaggregation and enhanced emission from the systems. Furthermore, the embedding of the PDI⋅18-C-6 complexes in poly(vinyl alcohol) (PVA) films generated remarkably high emission quantum yields (60-70 %) from the PDI derivatives. More importantly, the host-guest systems were tested for their ability to conduct electricity in PVA films. The electrical conductivities of the self-assembled systems in PVA were measured by electrochemical impedance spectroscopy (EIS) and the highest conductivity observed was 2.42×10(-5) S cm(-1) .

Nucleophilic Nitration of Arynes by Sodium Nitrite and its Multicomponent Reaction Leading to Double-Functionalized Arenes.

An unusual nucleophilic nitration of arynes by NaNO2 in the presence of water has been developed, and the concept was further demonstrated to accomplish a double functionalization of arynes using a multicomponent reaction protocol to synthesize pharmaceutically important (2-nitrophenyl)methanol derivatives. Such substitution ortho to -NO2 is difficult by other means. The reaction conditions are mild and avoid the use of strong acids, expensive transition metal catalysts, and additives.

ChemInform Abstract: Catalyst‐Free Dehydrative SN1‐Type Reaction of Indolyl Alcohols with Diverse Nucleophiles “on water”.

AbstractIndolyl methanol derivatives undergo an efficient dehydrative SN1‐type reaction with a variety of nucleophiles using water as the solvent, affording versatile 3‐indolyl derivatives in high yields.

Synthesis and Pharmacology of (Pyridin-2-yl)methanol Derivatives as Novel and Selective Transient Receptor Potential Vanilloid 3 Antagonists.

Transient receptor potential vanilloid 3 (TRPV3) is a Ca(2+)- and Na(+)-permeable channel with a unique expression pattern. TRPV3 is found in both neuronal and non-neuronal tissues, including dorsal root ganglia, spinal cord, and keratinocytes. Recent studies suggest that TRPV3 may play a role in inflammation, pain sensation, and skin disorders. TRPV3 studies have been challenging, in part due to a lack of research tools such as selective antagonists. Herein, we provide the first detailed report on the development of potent and selective TRPV3 antagonists featuring a pyridinyl methanol moiety. Systematic optimization of pharmacological, physicochemical, and ADME properties of original lead 5a resulted in identification of a novel and selective TRPV3 antagonist 74a, which demonstrated a favorable preclinical profile in two different models of neuropathic pain as well as in a reserpine model of central pain.

BH3 Activation by Phosphorus-Stabilized Geminal Dianions: Synthesis of Ambiphilic Organoborane, DFT Studies, and Catalytic CO2 Reduction into Methanol Derivatives

The reaction of the geminal dianion (SCS)2– 1 with 2 equiv of BH3·SMe2 leads to the isolation and full characterization of the new organoborane [(SCS)BH2][Li(THF)2] 2, in which the C═B bond possesses ambiphilic, multiple character. Treatment of 2 with another 1 equiv of BH3·SMe2 allows the isolation of the rare cyclic diborane species [(SCS)B2H5][Li(OEt2)] 4. The electronic structures of both compounds were investigated by means of DFT calculations. Compound 4 is an efficient catalyst for the reduction of CO2 to methanol derivatives by BH3·SMe2. A TON of ca. 2800 (TOF = 127 h–1) was achieved using 0.1 mol % of 4 in THF.

ChemInform Abstract: A Metal Catalyst‐Free and One‐Pot Synthesis of (3,4‐Dihydro‐2H‐benzo[b][1,4]oxazin‐2‐yl)methanol Derivatives in Water

Abstractstarting from various aminophenols and epichlorhydrin

С-ОН bond cleavage initiated by electron transfer: electroreduction of 9-fluorenol

Сyclic voltammetry, chronoamperometry, coulometry, electrolysis, digital simulation, quantum chemical calculations of 9-fluorenol as an example, were used to show that the electroreduction of aryl derivatives of methanol in 0.1M Bu4NClO4/DMF proceeds via the ECE mechanism (including the stages of radical anion formation and the COH bond cleavage in the radical anion) complicated by the reactions of the depolarizer with the anionic products. Among these reactions are the deprotonation of 9-fluorenol and its monoanions by hydroxide anion and fluorenyl anion. The thermodynamic parameters of the reactions have been estimated both theoretically and experimentally. It was found that the equilibrium constants of the fluorenyl anions deprotonation are close (C-anion) or higher (O-anion) than that of fluorenol. As a result the total equilibrium is shifted towards the side of the dianion of 9-fluorenone. The unusual ratio of the equilibrium constants was explained by lower basicity of π*-dianion compare with other anions.

Metal-free disproportionation of formic acid mediated by organoboranes.

In the presence of dialkylboranes, formic acid can be converted to formaldehyde and methanol derivatives without the need for an external reductant. This reactivity, in which formates serve as the sole carbon and hydride sources, represents the first example of the disproportionation of formate anions under metal-free conditions. Capitalizing on both experimental and computational (DFT) mechanistic considerations, the role of transient borohydride is highlighted in the reduction of formates and this reactivity was further exemplified in the methylation of TMP (2,2,6,6-tetramethylpiperidine) and in the transfer hydroboration reactions for the reduction of aldehydes.

Copper(II) Complexes Containing N,N′‐Bidentate N‐(Pyridin‐2‐ylmethyl)aniline and Its Derivatives: Synthesis, Structure and Magnetic Property

The reaction between [CuCl2 . 2H2O] and N,N′‐bidentate N‐(pyridin‐2‐ylmethyl)aniline (La ) and its derivatives (Lb and Lc ) in methanol yielded new Cu(II) complexes; namely polynuclear [CuLaCl2 ]n , dinuclear [CuLb (μ‐Cl)Cl]2 , and mononuclear [CuLcCl2 ], respectively. Monomeric [CuLcCl2 ] showed a distorted square planar geometry around copper metal‐based on X‐ray crystallography. The polymeric [CuLaCl2 ]n and dimeric [CuLb (μ‐Cl)Cl]2 had a chloro‐bridged five‐coordinated and a distorted square pyramidal geometry around the Cu(II) center. The Cu∙∙∙Cu′ distance was 3.915(1) Å in [CuLaCl2 ]n and 3.928(1) Å in [CuLb (μ‐Cl)Cl]2 . Interestingly, magnetic susceptibility (χ) measurements of complexes [CuLaCl2 ]n and [CuLb (μ‐Cl)Cl]2 exhibited a weak antiferromagnetic interaction.