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Numerical simulation of CO2 addition effects to fuel and oxidizer streams on flame structure has been conducted with detailed chemistry in H2–O2 diffusion flames of a counterflow configuration. An artificial species, which displaces added CO2 in the fuel- and oxidizer-sides and has the same thermochemical, transport, and radiation properties to that of added CO2, is introduced to extract pure chemical effects in flame structure. Chemical effects due to thermal dissociation of added CO2 causes the reduction flame temperature in addition to some thermal effects. The reason why flame temperature due to chemical effects is larger in cases of CO2 addition to oxidizer stream is well explained though a defined characteristic strain rate. The produced CO is responsible for the reaction, CO2+H=CO+OH and takes its origin from chemical effects due to thermal dissociation. It is also found that the behavior of produced CO mole fraction is closely related to added CO2 mole fraction, maximum H mole fraction and its position, and maximum flame temperature and its position. Copyright © 2003 John Wiley & Sons, Ltd.

In this research, a new class of pyrrolo[2,1-a]isoquinolinone derivative 7 was prepared. C-4 Hydroxylated 5-ethoxylactam 1b gave 4,5-epoxylactam 2 in high yield instead of isoquinoline derivative 3b under the N-acyliminium ion cyclization condition. The 4,5-epoxylactam 2 was converted to another N-acyliminium ion precursor 6 through base-promoted epoxide ring opening, silylation, and thermal Diels–Alder reaction with cyclopentadiene in high yield. Finally, compound 6 was cyclized in the presence of TiCl4 to provide cyclopentene-fused pyrroloisoquinoline derivative 7.

Interfering with microtubule dynamics is a validated approach for anticancer treatment and by selectively targeting the colchicine binding site on tubulin, microtubule destabilizing agents can evade mechanisms of drug resistance that commonly develop with other antimitotic agents such as taxanes and vinca alkaloids. We have recently reported the discovery of a potent and metabolically stable tubulin inhibitor (DJ101) that specifically targets the colchicine binding site on the beta tubulin subunit, disrupts tubulin polymerization and effectively circumvents drug efflux pumps that decrease the efficacy of existing tubulin inhibitors. To further pre-clinically evaluate DJ101 as a novel tubulin inhibitor and confirm its mechanism of action, we first visually demonstrated the ability of DJ101 to disrupt microtubule dynamics and elucidated the changes in microtubule structure and cell morphology through immunofluorescence techniques. Furthermore, we solved the crystal structure of DJ101 in complex with tubulin to determine its molecular interactions with the protein. We then demonstrated the significant in vitro potency of DJ101 against a panel of metastatic melanoma cell lines harboring major clinically relevant mutations observed in tumors and also validated its cytotoxicity against a broader array of NCI-60 cell lines. Further analysis revealed that DJ101 effectively thwarted anchorage-dependent melanoma colony formation and drastically hindered cell mobility and motility of those cancer cells. We further ascertained that DJ101 shows negligible off-target effects for major physiologically important receptors and ion channels, suggesting a good safety profile. Encouraged by the preliminary results from our in vitro assessment, we evaluated the in vivo activity of DJ101 in two different mouse models. At a dose of 30 mg/kg via i.p. injections, DJ101 nearly completely suppressed tumor growth in a human A375 melanoma xenograft model. It also appreciably inhibited metastasis potential in a murine B16F10 lung metastasis model at the same dose. In conclusion, we have described a microtubule destabilizing agent that targets the colchicine binding site on tubulin, confirmed its mechanism action, determined its potency in a vast array of cancer cell lines, particularly metastatic melanoma, demonstrated its inhibitory effect on cellular proliferation, motility and migration, and evaluated its anticancer potential in terms of tumor growth inhibition and metastasis in two in vivo models. Our findings offer a compelling rationale to further develop and advance DJ101 as a tubulin inhibitor for cancer therapy. Citation Format: Kinsie Arnst, Dong-Jin Hwang, Duane D. Miller, Wei Li. Novel tubulin inhibitor DJ101 targets the colchicine binding site and suppresses melanoma growth and metastasis [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 3223. doi:10.1158/1538-7445.AM2017-3223

The secreted anthrax toxin consists of three components: the protective antigen (PA), edema factor (EF) and lethal factor (LF). LF, a zinc metalloproteinase, compromises the host immune system primarily by targeting mitogen-activated protein kinase kinases in macrophages. Peptide substrates and small-molecule inhibitors bind LF in the space between domains 3 and 4 of the hydrolase. Domain 3 is attached on a hinge to domain 2viaresidues Ile300 and Pro385, and can move through an angular arc of greater than 35° in response to the binding of different ligands. Here, multiple LF structures including five new complexes with co-crystallized inhibitors are compared and three frequently populated LF conformational states termed `bioactive', `open' and `tight' are identified. The bioactive position is observed with large substrate peptides and leaves all peptide-recognition subsites open and accessible. The tight state is seen in unliganded and small-molecule complex structures. In this state, domain 3 is clamped over certain substrate subsites, blocking access. The open position appears to be an intermediate state between these extremes and is observed owing to steric constraints imposed by specific bound ligands. The tight conformation may be the lowest-energy conformation among the reported structures, as it is the position observed with no bound ligand, while the open and bioactive conformations are likely to be ligand-induced.

Seven phenylpropanoid glycosides named acteoside (1), acteoside isomer (2), leucosceptoside A (3), plantainoside C (4), jionoside D (5), martynoside (6), and isomartynoside (7) were isolated from Clerodendron trichotomum. Compounds 1 and 2 showed potent inhibitory activities against HIV-1 integrase with IC50 values of 7.8 +/- 3.6 and 13.7 +/- 6.0 microM, respectively.

Human immunodeficiency virus (HIV) integrase (IN) catalyzes the integration of HIV DNA copy into the host cell DNA. Such integration is essential for the production of progeny viruses, and therefore therapeutic agents that can inhibit this process should be effective anti-HIV agents. We have previously reported the inhibitory activity of dicaffeoylglucosides against HIV IN. In the present study, we have synthesized and tested dicaffeoyl or digalloyl compounds joined through a five-membered heterocyclic ring as HIV IN inhibitors to explore the SARs of this family of compounds. The starting heterocyclic diols were prepared from L-tartaric acid, diethyl L-tartarate or D-(+)-ribonic gamma-lactone. We found that the HIV IN inhibitory activities of dicaffeoyl derivatives were comparable to that of L-chicoric acid (IC(50)=24.9 microM). On the other hand, digalloyl derivatives were more potent than L-chicoric acid with IC(50) values of 4.7--15.6 microM.

The objective of these studies was to examine the murine pharmacokinetics, pharmacodynamics and metabolism of (3-(1H-indol-2-yl)phenyl)(1H-indol-2-yl)methanone (Indole 15), a novel tubulin inhibitor for the treatment of cancer. We developed HPLC and LC/MS/MS assays to quantitate Indole 15 and characterize its metabolites in vivo. Pharmacokinetic studies were performed after intravenous (IV), oral (PO) and subcutaneous (SC) administration of 10 mg/kg doses to male ICR mice. Urine and fecal samples were also collected over a 72-h period to identify metabolites. Pharmacodynamic studies were conducted by monitoring the tumor size change during a period of two weeks in PC-3 tumor bearing mice after daily IV administration of Indole 15 at doses of 0, 10, 50, 100 and 150 mg/kg. The pooled plasma concentration data after administration via different dose routes was simultaneously fitted by a two-compartmental model. Indole 15 was moderately well absorbed after PO and SC administration, with a bioavailable fraction of 0.27 and 0.72, respectively. The steady state volume distribution (Vss) and clearance (CL) were estimated to be 7.0 l/kg and 4.36 l/h/kg, respectively. The mean data of PC-3 tumor growth in mice was fitted well by a transduction model using fixed plasma pharmacokinetics as a driving function. Analysis of the metabolites in mice indicated that the compound undergoes extensive oxidative metabolism with subsequent sulfation. These studies demonstrate that favorable pharmacokinetic and pharmacodynamic properties of Indole 15 offer hope for achieving pharmacological activity in early clinical trials.

In this research, a new class of pyrrolo[2,1-a]isoquinolinone derivative 7 was prepared. C-4 Hydroxylated 5-ethoxylactam 1b gave 4,5-epoxylactam 2 in high yield instead of isoquinoline derivative 3b under the N-acyliminium ion cyclization condition. The 4,5-epoxylactam 2 was converted to another N-acyliminium ion precursor 6 through base-promoted epoxide ring opening, silylation, and thermal Diels–Alder reaction with cyclopentadiene in high yield. Finally, compound 6 was cyclized in the presence of TiCl4 to provide cyclopentene-fused pyrroloisoquinoline derivative 7.

Microtubules are one of the most useful subcellular targets in chemotherapy. We identified a novel indole, (3-(1H-indol-2-yl)phenyl)(1H-indol-2-yl)methanone (15), that inhibits tubulin action and exhibits potent antitumor activity in various preclinical models.In vitro cancer cell growth inhibition was measured by SRB or MTT assay in human cancer cell lines. Apoptosis induced by 15 was examined in LNCaP and PC-3 cells. Effects of 15 on cell cycle distribution and tubulin were investigated via in vitro models. In vivo toxicity and xenograft efficacy studies were conducted in mice.Indole 15 inhibited the in vitro growth of a number of human cancer cell lines, including drug-resistant cell lines that over-express P-glycoprotein, multidrug resistance-associated proteins, and breast cancer resistance protein with IC(50) values in the range of 34-162 nM. Nanomolar concentrations of the compound caused down-regulation of bcl-2, induced PARP cleavage, and induced apoptosis in both LNCaP and PC-3 prostate cancer cells, as confirmed by anti-histone ELISA and DNA laddering. In vitro studies revealed that the compound inhibited polymerization of purified tubulin and induced a strong and concentration-dependent G(2)M arrest in PC-3 cells. In vivo studies in immunodeficient mice bearing PC-3 tumor xenografts showed that the compound effectively inhibited tumor growth.The potent in vitro and in vivo antitumor activities of this novel indole suggest that drugs with this novel chemical scaffold might be developed for treatment of drug-resistant prostate cancer.

Interest in the development and therapeutic potential of nonsteroidal tissue-selective androgen receptor modulators (SARMs) has increased dramatically within the past decade. Rapidly expanding knowledge of nuclear hormone receptor structure and function and successful proof-of-principle clinical trials with SARMs have revived an almost dormant search for improved androgens. This Award Address attempts to chronicle the landmark discoveries (with emphasis on our work), organize the SARM landscape into clinically relevant bins, and provide insight into the clinical prospects for SARMs. 1.1. Origins of Androgen Use. An early (1889) and unusual experiment in androgen therapy was performed by Charles Edouard Brown-Sequard, age 72. He administered a testicular extract to himself and reported that he felt “increased vigor and capacity for work”. Despite retrospective suggestions that any effect was purely placebo, this report resulted in widespread use of testicular extracts throughout Europe and North America for several decades. Attempts to isolate the active components of testicular extract failed until 1935 when testosterone (17 hydroxy-4-andosten-3-one) was isolated from bull testes. Shortly thereafter, its synthesis was reported. In the same year, extracts of urine from males were shown to cause nitrogen retention, an indicator of anabolic metabolism. Testosterone was the first anabolic androgen to be used clinically, but its use is limited by its androgenicity and pharmacokinetic (PK) issues. 1 In the latter half of the 20th century, the chemical scaffold of testosterone was modified extensively, producing many

Diabetes is a disease that affects over 150 million people worldwide for which there are multiple oral and injectable medications. Because of trends in obesity and sedentary lifestyles, diabetes rates in both developed and developing countries are increasing at an alarming rate. Current medications are not adequately effective in maintaining long-term glycemic control in most patients, even when used in combination, leaving diabetics susceptible to developing life threatening and debilitating complications such as cardiovascular disease, blindness, kidney complications, and amputations. Consequently, there is a critical need for more potent pharmacotherapies with novel mechanisms of action. A panel of 20 emerging diabetes targets is presented, and small molecule modulators for each target will be discussed.

Selective androgen receptor modulators (SARMs) are essentially prostate sparing androgens, which provide therapeutic potential in osteoporosis, male hormone replacement, and muscle wasting. Herein we report crystal structures of the androgen receptor (AR) ligand-binding domain (LBD) complexed to a series of potent synthetic nonsteroidal SARMs with a substituted pendant arene referred to as the B-ring. We found that hydrophilic B-ring para-substituted analogs exhibit an additional region of hydrogen bonding not seen with steroidal compounds and that multiple halogen substitutions affect the B-ring conformation and aromatic interactions with Trp741. This information elucidates interactions important for high AR binding affinity and provides new insight for structure-based drug design.

A new series of androgen receptor targeted agents (ARTA) was prepared and tested in androgen-dependent and -independent prostate cancer cell lines. These agents were bicalutamide analogs with isothiocyanato substituted B-rings. Also, the linker sulfone of R-bicalutamide was maintained or replaced with several alternative linkages including ether, amine, N-methylamine, thioether, and methylene (in this case the product was a racemic mixture) functional groups at the X-position. To expand the structure–activity relationship (SAR) of these arylisothiocyanato AR ligands, B-ring halogenated arylisothiocyanato ligands were also prepared and tested. The arylisothiocyanato AR ligands showed strong binding affinities to AR ranging from 0.6 to 54 nM. Among them, thioether and ether linkages demonstrated high binding affinities (0.6 and 4.6 nM, respectively) and selective cell growth inhibition (approximately 3- to 6-fold) for LNCaP, an androgen-dependent prostate cancer cell line, when compared to the androgen independent prostate cell lines (DU145, PC-3, and PPC-1) and a bladder cell line (TSU-Pr1). However, the ligands were inactive (IC50>100 mM) in a normal monkey kidney cell line (CV-1) that was used as the control for non-specific toxicity.

The recent discovery of nonsteroidal selective androgen receptor modulators (SARMs) provides a promising alternative for testosterone replacement therapies, including hormonal male contraception. The identification of an orally bioavailable SARM with the ability to mimic the central and peripheral androgenic and anabolic effects of testosterone would represent an important step toward the "male pill". We characterized the in vitro and in vivo pharmacologic activity of (S)-3-(4-chloro-3-fluorophenoxy)-2-hydroxy-2-methyl-N-(4-nitro-3-trifluoromethylphenyl)propionamide (C-6), a novel SARM developed in our laboratories. C-6 was identified as an androgen receptor (AR) agonist with high AR binding affinity (K(i) = 4.9 nM). C-6 showed tissue-selective pharmacologic activity with higher anabolic activity than androgenic activity in male rats. The doses required to maintain the weight of the prostate, seminal vesicles, and levator ani muscle to half the size of the maximum effects (i.e., ED(50)) were 0.78 +/- 0.06, 0.88 +/- 0.1, and 0.17 +/- 0.04 mg/day, respectively. As opposed to other SARMs, gonadotropin levels in C-6-treated groups were significantly lower than control values. C-6 also significantly decreased serum testosterone concentration in intact rats after 2 weeks of treatment. Marked suppression of spermatogenesis was observed after 10 weeks of treatment with C-6 in intact male rats. Pharmacokinetic studies of C-6 in male rats revealed that C-6 was well absorbed after oral administration (bioavailability 76%), with a long (6.3 h) half-life at a dose of 10 mg/kg. These studies show that C-6 mimicked the in vivo pharmacologic and endocrine effects of testosterone while maintaining the oral bioavailability and tissue-selective actions of nonsteroidal SARMs.