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Parkinson's disease (PD) is associated with elevated levels of hMAO-B in the brain, and MAO-B has been recognized a successful target for developing anti-PD drugs. Herein we report rasagiline derivatives as novel potent and selective hMAO-B inhibitors. They were designed by employing fragment-based drug design strategy to link rasagiline and hydrophobic fragments, which may target a hydrophobic pocket in the entrance cavity of hMAO-B. Different linkers such as -OCH 2 -, -SCH 2 -, -OCH 2 CH 2 -, -OCH 2 CH 2 O-, -OCH 2 CH 2 CH 2 O- were tried. A promising selective hMAO-B inhibitor D14 with similar inhibitory activity as rasagiline and improved isoform selectivity was yielded. The selectivity profile of compounds reported herein suggests that we can further develop more potent hMAO-B inhibitors with high isoform selectivity through this strategy., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Preclinical models of inflammatory diseases (e.g., neuropathic pain, rheumatoid arthritis, and multiple sclerosis) have pointed to a critical role of the chemokine receptor 2 (CCR2) and chemokine ligand 2 (CCL2). However, one of the biggest problems of high-affinity inhibitors of CCR2 is their lack of efficacy in clinical trials. We report a new approach for the design of high-affinity and long-residence-time CCR2 antagonists. We developed a new competition association assay for CCR2, which allows us to investigate the relation of the structure of the ligand and its receptor residence time [i.e., structure-kinetic relationship (SKR)] next to a traditional structure-affinity relationship (SAR). By applying combined knowledge of SAR and SKR, we were able to re-evaluate the hit-to-lead process of cyclopentylamines as CCR2 antagonists. Affinity-based optimization yielded compound 1 with good binding (Ki = 6.8 nM) but very short residence time (2.4 min). However, when the optimization was also based on residence time, the hit-to-lead process yielded compound 22a, a new high-affinity CCR2 antagonist (3.6 nM), with a residence time of 135 min.

The title molecular salt, C(8)H(12)N(+)·C(26)H(21)O(3)(-), contains a dimeric indane pharmacophore that demonstrates potent anti-inflammatory activity. The indane group of the anion exhibits some disorder about the α-C atom, which appears common to many structures containing this group. A model to account for the slight disorder was attempted, but this was deemed unsuccessful because applying bond-length constraints to all the bonds about the α-C atom led to instability in the refinement. The absolute configuration was determined crystallographically as S,S,S by anomalous dispersion methods with reference to both the Flack parameter and Bayesian statistics on Bijvoet differences. The configuration was also determined by an a priori knowledge of the absolute configuration of the (1S)-1-phenylethanaminium counter-ion. The molecules pack in the crystal structure to form an infinite two-dimensional hydrogen-bond network in the (100) plane of the unit cell.

Background: CC chemokine receptor 2 (CCR2) is a GPCR involved in the migration and activation of inflammatory monocytes. A number of studies have highlighted a role for CCR2 in preclinical animal models of atherosclerosis, restenosis, multiple sclerosis, rheumatoid arthritis and insulin resistance. Accordingly, pharmaceutical scientists have been investigating the antagonism of CCR2 as a potential therapy., Objective: This patent evaluation examines the report of a new chemical subseries of CCR2 antagonists., Methods: The compounds of the title invention are compared to the related earlier work in the area of CCR2 antagonism., Conclusions: The compounds disclosed in PCT application WO 2009023754 extend previous work in a dipiperidine series of CCR2 antagonists through the introduction of both a 1,2-disubstituted ethanol spacer and a 1'H-spiro[indene-1,4'-piperin]-1'-yl group. These compounds may represent a means of treating diseases driven by CCR2-bearing leukocytes.

A series of aryl- and aroyl-substituted chalcone analogues of the tubulin binding agent combretastatin A4 (1) were prepared, using a recently introduced one-pot palladium-mediated hydrostannylation-coupling reaction sequence. These chalcones were converted to indanones by Nazarov cyclisation, followed by oxidation to give the corresponding indenones. Indenones were also prepared using a palladium-mediated formal [3+2]-cycloaddition process between ortho-halobenzaldehydes and diarylpropynones. All compounds were assessed as inhibitors of tubulin polymerisation, but only E-31 had activity similar to that of 1. However, compound E-31 did not exhibit antiproliferative activity against the MCF-7 cell line.

Elevated plasma aldosterone levels play a detrimental role in certain forms of congestive heart failure and myocardial fibrosis. We proposed aldosterone synthase (CYP11B2) as a novel target for the treatment of these diseases. In this study, the synthesis and biological evaluation of substituted E- and Z-imidazolylmethylenetetrahydronaphthalenes and E- and Z-imidazolylmethyleneindanes (compounds 1a,b-9a,b) is described. The compounds were prepared by a Wittig-like reaction. They were tested for activity using bovine CYP11B and human CYP11B2 expressed in fission yeast and V79 MZh cells. Selectivity was determined toward human CYP11B1, CYP19, and CYP17. Especially in the case of CYP11B1 (steroid 11beta-hydroxylase), selectivity is a crucial issue, since sequence homology between this enzyme and the target enzyme is very high (93%). On the basis of the X-ray structure of human CYP2C9, a protein model of CYP11B2 was developed and docking experiments with the title compounds were performed. The biological results revealed highly potent inhibitors of CYP11B2 (IC(50) = 4-93 nM). The Z-isomers usually were more active than the corresponding E-isomers. Different inhibitory profiles could be observed: rather selective inhibitors of CYP11B1, dual inhibitors of both enzymes, and rather selective inhibitors of CYP11B2. The chloro derivative 8b was found to be a highly potent CYP11B2 inhibitor (IC(50) = 4 nM) showing a 5-fold selectivity for CYP11B1 (IC(50) = 20 nM). This compound could be an interesting lead for further optimization as a therapeutic agent. It also could be used as well as the CYP11B1 selective compounds as a pharmacological tool.

The synthesis and biological activities of biarylamide-substituted diaminoindanes as microsomal triglyceride transfer protein (MTP) inhibitors are described. One of the more potent compounds, 8aR, inhibited both the secretion of apoB from Hep G2 cells and the MTP-mediated transfer of triglycerides between synthetic acceptor and donor liposomes with IC(50) values of 0.7 and 70 nM, respectively. In normolipidemic rats and dogs, oral administration of 8aR dose-dependently reduced both plasma triglycerides and total cholesterol. Moreover, in rats and dogs, 8aR also prevented the postprandial rise in plasma triglycerides following a bolus administration of a fat load. Because MTP inhibitors decrease very low density lipoprotein assembly in the liver, the potential for hepatic lipid accumulation was evaluated. In normolipidemic rats, hepatic cholesterol and triglyceride contents were dose-dependently increased by 8aR. However, hepatic lipid accumulation resulted in negligible change in total liver weight and was reversible after withdrawal of the compound.

The effects of an orally active inhibitor (UK 79300) of the neutral metalloendopeptidase EC 3.4.24.11 were investigated in six healthy male volunteers maintained on a constant diet (150 mmol sodium/day and 80 mmol potassium/day). Subjects were studied in a random order, single-blind study on two occasions, each 48 hours in length, when they were given UK 79300 (25 or 50 mg p.o.) or placebo at 12-hour intervals (each agent for 24 hours). The endopeptidase inhibitor enhanced plasma concentrations of atrial natriuretic factor in association with suppression of both plasma renin activity and aldosterone concentrations. Twenty-four-hour urinary excretion of sodium was doubled by UK 79300, and the urinary excretion rates of phosphorus, atrial natriuretic factor immunoreactivity, and cyclic guanosine monophosphate were also significantly enhanced, whereas urinary aldosterone excretion was halved. The profile of biological effects closely paralleled those previously reported with low dose infusions of atrial natriuretic factor in humans and animals. Therapeutic trials of such inhibitors are now indicated for hypertension or heart failure together with further studies to clarify the underlying mechanisms of action.

Racemic indacrinone is a potent loop diuretic with transient uricosuric properties in certain nonhuman primates and in man. After chronic treatment, hyperuricemia develops presumably because of enhanced proximal tubular urate reabsorption secondary to extracellular fluid volume contraction. The natriuretic and uricosuric activities are associated with both enantiomers, but the (-)-enantiomer is significantly more potent as a natriuretic agent than the (+). Acutely, in Cebus monkeys, both enantiomers appear to have similar uricosuric activity. The difference in the natriuretic potency between the two enantiomers provides the possibility of altering the enantiomer ratio from its naturally occurring 1:1 ratio to another combination which would enhance the uricosuric action [more (+) relative to (-)] while preserving the potent natriuretic action of the (-). In healthy volunteers, a 1:4 ratio [(-):(+)] was isouricemic after 7 days of treatment and a 1:8 mixture lowered mean serum urate by 13%. Presumably, the desired ratio of (-):(+) will be in the range 1:4-1:9. Further enhancement of the diuretic profile of this compound may be obtained by adding sufficient amiloride to produce isokalemia.

The renal effects of a new, substituted indanyloxyacetic acid diuretic agent were evaluated in 16 anesthetized rats using micropuncture and clearance techniques. Glomerular filtration rate, mean arterial pressure and hematocrit remained unchanged. Urine flow increased 13 times after i.v. administration of 50 mg/kg b.wt. of the diuretic. Sodium excretion increased from 0.4 +/- 0.05% of the amount filtered to 6.62+/-0.87%. Potassium urine/plasma concentration ratio declined 6-fold while potassium excretion nearly doubled. Proximal tubular reabsorption was not altered significantly by this indanone diuretic. Reabsorption was markedly inhibited between late proximal and early distal micropuncture sites, that is, in the loop of Henle. The diuretic did not appear to interfere with normal distal tubular function. In the collecting tubules, reabsorption was markedly reduced from 41+/-0.2 mul/min/100 g b.wt. to 26+/-5 (with P less than .005). This new indanone compound appears to be a potent, specific natriuretic diuretic agent which inhibits tubular reabsorption primarily in the loop of Henle and collecting tubules, that is, in distal nephron segments located deep within the kidney. It produces a somewhat delayed but prolonged diuresis in the rat.

The actions of 2-aminoindane, 2-amino-1,2,3,4-tetrahydronaphthalene and amphetamine and their N-methyl and NN-dimethyl derivatives on the guinea-pig ileum were compared. All, except the tertiary 2-aminoindane, inhibited the responses to electrical stimulation and it is suggested that this is not fully explained by their sympathomimetic properties. NN-Diemthyl-2-aminoindane increased these responses and caused contractions of the unstimulated ileum due to a nicotine-like action. The indane series was more effective in producing contractions of the ileum than the other compounds. The three tertiary derivatives antagonized competitively the actions of histamine on the ileum and those of 5-hydroxy-tryptamine on the rat uterus.

Administration of RDS-127 (3.0 mg/kg) induced seminal emission within three minutes of IP injection and suppressed the display of penile reflexes in intact and spinally transected rats. In Experiment 1, RDS-127 was administered to intact, sexually experienced rats in a protocol previously demonstrated to selectively lower the ejaculatory threshold of copulating animals. The incidence of seminal emission was significantly elevated by RDS-127 but penile reflexes were present in only 8% of the drug-treated rats, compared to 59% of controls. In Experiment 2, seminal emission was induced 2.3 +/- 0.4 (S.E.) minutes from injection of RDS-127. Animals which responded to RDS-127 with multiple emissions had significantly lower ejaculation latencies during copulatory tests conducted prior to drug treatment than animals which had no or only single seminal emissions following RDS-127 injection. Spontaneous seminal emission in the 3 day period initiated 2 hours after RDS-127 injection was unaffected by the drug. Spontaneously produced plugs were approximately twice the weight of those induced by RDS-127. In Experiment 3, seminal emission was induced in spinally transected rats 1.7 +/- 0.4 minutes following RDS-127 administration, whereas drug treatment attenuated the enhancement of penile reflexes observed following midthoracic spinal transection. These experiments suggest that a spinally-mediated dopaminergic mechanism is capable of stimulating seminal emission acutely in the rat and inhibiting the display of penile reflexes by the supine animal.

A series of (omega-piperazinylalkoxy)indan derivatives has been synthesized and screened for potential antianxiety activities. The effect of structural modification of these molecules on activities has been systemically examined. Antianxiety activity was displayed by 5-[3-(4-phenyl-1-piperazinyl)propoxy]indan (2), 5-[3-[4-(4-fluorophenyl)-1-piperazinyl]-propoxy]indan (8), 6-fluoro-5-[3-(4-phenyl-1-piperazinyl)propoxy]indan (33), and 6-methyl-5-[3-(4-phenyl-1-piperazinyl)propoxy]indan (42), as determined in antifighting and anti-morphine tests. These derivatives in antianxiety tests were equipotent or more potent than chlordiazepoxide with less muscle-relaxant effect. They also showed weak neuroleptic-like action.

Norepinephrine N-methyltransferase from rat brain stem was inhibited in vitro by 1-aminoindans with chlorine substituents on the aromatic ring. The order of inhibitory potency among these compounds was 4.5-dichloro greater than 4-chloro greater than 5-chloro approximately or equal to 5,6-dichloro approximately or equal to 6,7-dichloro greater than 6-chloro greater than 7-chloro. All except the 7-chloro compound were more potent inhibitors than the parent unsubstituted 1-aminoindan. 4,5-Dichloro-1-aminoindan was a competitive inhibitor in kinetic studies with L-norepinephrine as the variable substrate; its Ki value determined from a Dixon plot was 3.3 x 10(-7) M. At doses of 10-40 mg/kg i.p., this compound inhibited brain stem and hypothalamic norepinephrine N-methyltransferase in vitro and lowered hypothalamic concentrations of epinephrine in rats, effects that lasted for several hours. 4,5-Dichloro-1-aminoindan may be a useful pharmacologic tool for studies of epinephrine-forming neurons in brain.

Pharmacologic dopamine receptor stimulation by RDS-127 (2-N,N-di-n-propylamino-4,7-dimethoxyindane) resulted in qualitatively different changes in the mating pattern depending on the dose administered and time elapsed between treatment and behavioral observation. A low dose (0.25 mg/kg) selectively increased the latency to ejaculation whereas a high dose (3.0 mg/kg) decreased ejaculation latency and intromission frequency (both indicators of ejaculatory efficiency) when behavioral observations were begun 30 minutes after intraperitoneal administration. Intermediate doses (0.5, 1.0, and 2.0 mg/kg) did not alter the time required to achieve ejaculation but did lower the number of intromissions preceding ejaculation. These dose-dependent actions resemble the effects of dopaminomimetics (reported by others) on locomotor activity. When mating tests were conducted shortly (less than five minutes) after drug administration, the induction of ejaculation by the high dose was enhanced. At this time, as well as after a prolonged delay (two hours), signs of decreased arousal (longer intromission latencies) were also observed. However, the postejaculatory refractory period was altered in a time-dependent fashion, viz: it was shortened closest to the injection time, not altered 30 minutes after treatment, and increased two hours after RDS-127 administration. Finally, RDS-127 induced seminal emission (ex copula) in 2.9 +/- 0.9 (S.E.) minutes, and these emissions did not differ in weight from normal spontaneous (diurnal) seminal emissions. The RDS-127-induced seminal emission was not followed by a refractory period of similar magnitude to that seen after ejaculation in copula. The data are interpreted in terms of the involvement of dopamine receptor subtypes in the modulation of masculine sexual behavior.

A series of 1-piperazino-3-phenylindans was synthesized and tested for neuroleptic and thymoleptic activity. Neuroleptic activity was found only in trans racemates and was associated with one of the enantiomers only. The potent and long-acting neuroleptic compound trans-4-[3-(4-fluorophenyl)-6-(trifluoromethyl)indan-1-yl]-1-piperazineethanol (Lu 18-012, tefludazine) was developed by systematic variation of structural components. Thymoleptic activity was optimized, especially with respect to dopamine-uptake inhibition. No geometrical stereoselectivity was found with regard to dopamine-uptake inhibition, but a high enantioselectivity could be demonstrated for both cis and trans racemates. The most potent compounds were 1-piperazino-3-(3,4-dichlorophenyl)indans with IC50 values of about 2nM for inhibition of dopamine uptake.

Ten new compounds, N-aryl substituted piperazinealkylindanes, have been synthesized. The most active one 1-(2-[4-(3-chlorophenyl)-1-piperazinyl]-ethyl)-indane (compound 9), displayed evident central serotoninolytic properties in the 5-hydroxytryptamine (5-HTP) head twitch test in mice, as well as in the tryptamine convulsions test and the quipazine-stimulated hind paw flexor reflex test in rats.

The uncoupling activities of clidanac and its dechlorinated derivative on oxidative phosphorylation were examined using isolated rat liver mitochondria. Clidanac was found to uncouple the oxidative phosphorylation and no difference was detected in the uncoupling potency of the two enantiomorphs. Dechlorclidanac was significantly less effective in the uncoupling activity than clidanac.

Both prepubertal and adult rats were treated with a single oral dose of either 60 mg or 120 mg of dl-6-(N-pipecolinomethyl)-5-hydroxy indane maleate (PMHI) per kg of body weight. Their testicular weights were drastically reduced compared with those of the controls. A follow-up, beginning on the third day post-treatment and continuing for a period of 50 days, showed that the body weight growth of PMHI-treated rats was not retarded. The hormonal profile indicated that, except for FSH which showed a transitory elevation in PMHI-treated immature rats, the serum levels of LH, estrogen, and testosterone were indistinguishable from those of the controls. Testicular histology revealed that the spermatogenic process in PMHI-treated rats recovered at a dose-related rate. EM sections of testes of adult rats indicated that cytoplasmic vacuolation appeared in the Sertoli cells 5 h post-treatment. The consequent cascade of arrested spermiogenesis included abnormal acrosomal condensation of spermatids and sloughing of polynucleated spermatids. Some spermatocytes also seemed to be affected, but spermatogonia and Leydig cells remained intact. These results indicate the PMHI acts primarily on Sertoli cells and causes arrest in the spermiogenetic stage of the spermatids. At a higher and toxic dose of PMHI, however, the earlier germinal elements might also be affected, due to the extensive damage to the supporting Sertoli cells.

A series of substituted 2-aryl-1,3-indandiones were investigated for their ability to inhibit the complement system. Some of them were found to be considerably strong inhibitors. The inhibitory activity was mainly dependent on substitutions at positions 3 and 5 of the phenyl ring. 3,5-dichloro-(8), 3,5-bis(trifluoromethyl)- (7), 3,5-diisopropyl- (3) and 3,5-di-t-butyl- (5) phenylindandiones were the strongest inhibitors of the series. The generation of EAC1-5 cells from EAC1-3 cells and C5 was most strongly inhibited by these compounds although some inhibition of the interaction of EAC1-5 with C6-C9 and EAC1-6 with C7-C9 was also observed. Slight inhibition at other steps of complement activation was also seen but this was not considered to be appreciable. Dialysis of normal serum or purified C5 pre-incubated with compounds 3, 5, 7 and 8 did not cause recovery of the hemolytic activity of normal serum or purified C5. Thus, the main site of inhibition in the complement cascade appeared to be at C5. The total alternative pathway was also inhibited to some extent by these compounds, probably due to their interaction with C5.

The saluretic and uricosuric responses elicited by a novel agent, MK-196, have been studied in a great ape, the chimpanzee. This agent is orally active at very low doses and has a prolonged duration of action. Probenecid does not appear to influence the saluretic and uricosuric properties of MK-196. Net tubular secretion of urate was reduced by MK-196. Urinary pH changes did not compromise the efficacy of this new agent. On a dose basis, MK-196 was more saluretic (and uricosuric) than ethacrynic acid or furosemide and possessed a longer duration of action. Because of the marked natriuresis caused by MK-196, some increase in potassium excretion occurred.

Modification of food intake and motor activity was investigated following administration of amphetamine (AMP), apomorphine (APO) and three novel 2-aminoindanes (2-AI): 2-di-n-propylaminoindane (JPC-60-36), 2-di-n-propylamino-5,6-dimethoxyindane (JPC-211) and 2-di-n-propylamine-4,7-dimethoxyindane (RDS-127). These compounds demonstrated dose- and time-related inhibition of food intake in male rats which were habituated to eating 4 hr each day. The ranked potencies were as follows: RDS-127 greater than AMP = APO greater than JPC-60-36 and JPC-211 was inactive. 2-di-n-Propylamine-4,7-dimethoxyindane (RDS-127) did not increase motor activity in a dose range that Significantly inhibited food intake (66% of control intake with 0.08 mumol/kg). Food intake inhibition was blocked by pimozide, but not by propranolol or phentolamine. The anorectic-like actions of RDS-127 were long-lasting (greater than 4 hr) and RDS-127 was approximately 3-fold more potent than amphetamine or apomorphine in producing increased locomotor activity; the other 2-aminoindanes were less potent in producing hyperactivity. Hyperactivity responses were blocked by pimozide, but not by alpha-methyl-p-tyrosine. These results suggest that 2-aminoindanes may modify motor behaviors, at least in part, via direct stimulation of dopamine receptors. The structure-activity relationships of 2-aminoindanes on locomotor activity and inhibition of food intake are discussed.

The ability of 2-aminotetralins (2-ATs), 2-aminoindanes (2-AIs), morphine (M) and clonidine (CLON) to alter neuroeffector transmission was studied on field-stimulated (FS) guinea-pig ilea (GPI). The activity of these compounds to inhibit K+, histamine (H), actylcholine (ACh), nicotine (Nic) and serotonin (5-HT) induced contractions was determined using superfused GPI segments. 2-ATs, 2-AIs, M and CLON dose-dependently inhibited contractions produced by low frequency stimulation through alpha-adrenergic, opioid or unknown receptor mediated mechanisms. 2-ATs inhibited ACh, Nic, 5-HT and FS, but not K+- or H-induced contractions. 2-ATs, 2-Ais and M were more potent than hexamethonium in inhibiting Nic-induced contractures. 2-AT and 2-AI-induced inhibition was not antagonized by naloxone or phentolamine. However, the inhibitory effects of 2-ATs. 2-AIs and M on FS-GPI were antagonized by increasing the concentration of Ca2+ ion in the media. These data are consistent with the supposition that 2-ATs, 2-AIs or M alter neuroeffector transmission through competitive changes in Ca2+ disposition in cholinergic neurons of guinea-pig isolated ilea. A discussion relating other biological actions of 2-ATs or 2-AIs (e.g. alpha-adrenergic mediated antinociception) to the observed inhibitory neuroeffector responses is provided.

N-Alkylated derivatives of 2-amino-4,7-dimethoxyindan were prepared for evaluation of central and peripheral dopaminergic activity using biochemical and behavioral tests in the rat and cardiovascular responses in the cat. 2-(Di-n-propylamino)-4,7-dimethoxyindan (4e) demonstrated equal activity with apomorphine to activate peripheral presynaptic dopamine receptors. Central pre- and postsynaptic dopamine receptors were also activated with 4e. In contrast to the intense long-acting sympathomimetic actions previously reported for the 2-amino-5,8-dimethoxytetralins, these compounds produced weak, transient effects in heart rate and blood pressure. The majority of 2-amino-4,7-dimethoxyindan derivatives tested are weak or inactive pre- and postsynaptic dopamine receptor agonists.

The neurochemical profile of a new compound, Lu 19-005 [(+/-)trans-3-(3,4-dichlorophenyl)-N-methyl-1-indanamine hydrochloride], has been investigated. Lu 19-005 is a potent inhibitor of the synaptosomal uptake of 3,4-dihydroxyphenylethylamine (dopamine, DA), noradrenaline (NA), and 5-hydroxytryptamine (5-HT, serotonin). In this respect it resembles diclofensine, whereas compounds such as GBR 13.069 and bupropion are more selective DA-uptake inhibitors. Although Lu 19-005 releases DA in in higher concentrations it must be considered as an uptake inhibitor, as the accumulation of DA is inhibited in much lower concentrations. Lu 19-005 attenuates the DA and NA depletion caused by 6-hydroxydopamine in mouse brain. These properties confirm the DA- and NA-uptake-inhibitory properties of the compound. In receptor-binding models and functional in vitro tests Lu 19-005 is devoid of dopaminergic-, serotonergic-, noradrenergic-, histaminergic-, and cholinergic-inhibiting properties. Since DA, NA, and 5-HT seem to be involved in depression, the profile of Lu 19-005--with equally potent activity on the three neuronal systems--makes it an interesting experimental tool and a potential new antidepressant agent.

We have studied the effects of the two enantiomeric forms of the diuretic agent, indacrinone (MK-196), upon transport of sodium and potassium by the loop of Henle and distal tubule, using the technique of continuous microperfusion, in vivo, of individual tubular segments in the rat kidney. In the loop of Henle, both the (+)-and (-)-enantiomers, when included in the tubular perfusion fluid at a concentration of 5 X 10(-4) M, inhibited the reabsorption of sodium and potassium, but the (-)-enantiomer was significantly more effective in this regard than the (+)-enantiomer. Although loop sodium reabsorption was incompletely blocked by either form of the drug, potassium reabsorption by the loop was on average abolished by (-)-MK-196 and was actually converted in some experiments to an appreciable net secretory flux. In the distal tubule, both enantiomers inhibited net sodium reabsorption, but neither affected the control level of potassium secretion. These experiments provide direct evidence that the natriuretic effect of this agent is due to actions on sodium transporting sites in the loop of Henle and distal tubule. Furthermore, because potassium transport was affected only in the loop, they suggest that the nature of the cellular cation transport mechanism influenced by the drug may be different at the two nephron sites studied.

Pharmacological studies on the derivatives of 1-indancarboxylic acid yielded 4-benzoyl-1-indancarboxylic acid (TAI-901) and 4-(4-methylbenzoyl)-1-indancarboxylic acid (TAI-908). The relative potency (R.P.) of TAI-901 and TAI-908 assessed in parallel line assays (indomethacin - 1) demonstrated that both compounds were highly analgesic against various noxious stimuli induced in experimental animals. R.P. values of TAI-901 were 1.0, 1.7, 4.4 and 2.8 in the phenylquinone writhing, acetic acid writhing, adjuvant arthritic pain and urate arthritic pain tests, respectively. R.P. values of TAI-908 were 1.6, 2.0, 4.7 and 7.0, respectively, in these tests. Both compounds were more inhibitory than indomethacin against acute inflammation, but less inhibitory against chronic inflammation. The inhibitory activities of TAI-901 and TAI-908 on the prostaglandin biosynthesis by microsomes of rabbit renal medulla were 2.2 and 2.6 times that of indomethacin. TAI-901 was 1/3.8 1/7.1, and TAI-908 was 1/16.7 and 1/12.5 as toxic as indomethacin in male rats and mice, respectively.

Two series of N-substituted 2-aminoindan systems have been prepared: 4,5-dihydroxy-2-aminoindan (1) has a hydroxylation pattern analogous to the alpha conformer of dopamine, and 5,6-dihydroxy-2-aminoindan (2) has a hydroxylation pattern of the beta conformer of dopamine. All members of both series demonstrated only extremely weak binding to calf caudate homogenate. Certain N-alkylated 4,5-dihydroxyindans were violent emetics in the dog and were potent in blockade of the effect of stimulation of the cardioaccelerator nerve of the cat. In contrast, the 5,6-dihydroxy series displayed low or no activity/potency in these assays. Conformational analysis of the 2-aminoindan system is described and discussed.

Investigation of the chemistry of the potent new uricosuric diuretic indacrinone (MK-196) led to a class of novel annulated derivatives, indeno[5,4-b]furan-2-carboxylic acids. The structural requirements for optimal diuretic and uricosuric activity of the tricyclic analogues differed from those of their (indanyloxy)acetic acids counterparts. Most notably, the tricyclic analogues were two to four times more natriuretic than the corresponding (indanyloxy)acetic acids when administered orally to rats, and in chimpanzees, uricosuria was observed only in those indenofurans having a nuclear aryl substituent.

Three series of bicyclic, semirigid congeners of beta-phenethylamine have been prepared for evaluation of the effect of ring size (and of concomitant conformational variation) on biological activity in a variety of assays for adrenergic and dopaminergic actions. Pharmacologic activity was associated with 2-aminotetralin and 2-aminoindan derivateves, but was not found with 6-aminobenzocycloheptene derivatives. Noteworthy is the ability of several aminotetralins and aminoindans to increase the hot-plate reaction time without eliciting dopaminergic effects. This action was not blocked by pretreatment with naloxone.

Spiro[tetralin-2,2'-pyrrolidine] (13) and spiro[6-methoxytetralin-2,2'-pyrrolidine] (17) were prepared by initial Michael condensation of 2-nitrotetralin and 6-methoxy-2-nitrotetralin, respectively, with methyl acrylate to give 7 and 8, both of which could be reductively cyclized to 10 and 11, followed by LiAlH4 reduction. Spiro[indan-2,2'-pyrrolidine] (15) was prepared in an analogous manner form 2-nitroindan, and spiro[6-hydroxytetralin-2,2'-pyrrolidine] (19) was prepared by O-demethylation of 17. Compound 13 and its N-methyl derivative, 14, both showed good analgesic activity. Compounds 13-16 all possessed weak antidepressant properties, but neither 19 nor its N-methyl derivative 20 had any significant CNS activity.

The active methylene compounds acetylacetone, 1,1,1-trifluoroacetylacetone, benzoylacetone, dibenzoylmethane, and 1,3-indandione inhibited the mutagenicity of 2-nitrofluorene in Salmonella typhimurium. They also inhibited the N,O-acetyltransferase-catalyzed transfer RNA binding of N-hydroxy-2-acetylaminofluorene, but they did not inhibit N,O-acetyltransferase. However, only 1,3-indandione and 1,1,1-trifluoroacetylacetone significantly inhibited the binding of N-acetoxy-2-acetylaminofluorene to transfer RNA. Reaction of the trifluoro compound with the acetoxy compound yielded 1-(N-2-fluorenylacetamido)acetone. These results demonstrate that active methylene compounds can inhibit mutagenicity and nucleic acid binding of chemical carcinogens.

In conscious rabbits, the intravenous administration of pindolol (1.25 mg/kg), propranolol (1 mg/kg) and alprenolol (2 mg/kg) induced a highly significant decrease of mean arterial blood pressure and significant bradycardia. In the same model, the intravenous administration of saline, indomethacin, and clidanac did not affect the mean arterial blood pressure and heart rate. Pretreatment with indomethacin and clidanac reduced the effect of these beta-blockers on the mean arterial blood pressure and had no effect on the heart rate. Treating of the guinea pig heart homogenate with 1 microM indomethacin or clidanac decreased the number of beta-adrenoceptors without changing their affinity. These results suggest that indomethacin and clidanac interfere with beta-adrenoceptor-mediated effects.

Indacrinone, a drug chemically related to ethacrynic acid, usually stimulated reversibly short circuit current and sodium influx when applied to the epithelial surface of amphibian skin. Concomitantly, transepithelial conductance, gt, decreased, provided chloride was the main anion in the incubation fluid. Electrophysiological analysis including microelectrode impalement indicated that the drug increased the sodium-conductance at the apical border of the impaled (most likely granular) cells. The decrease in gt thus points at shunt conductance being reduced with indacrinone, sometimes drastically. Decrease of transepithelial chloride flux with the drug as well as lack of effect of the drug on gt in the absence of chloride on the epithelial side demonstrate the influence of indacrinone on a chloride specific pathway. Whether this is along a paracellular route or through a cellular compartment not coupled to granular cells (mitochondria-rich cells?) cannot be decided on the basis of the present data.

The spermicidal effect of eleven chelating agents with a ring structure was evaluated using human spermatozoa. All were potent spermicides in vitro. 4-Bromo-7-hydroxyindan oxime (S-11) was the most potent and its lowest effective concentration for immobilizing sperm within 20 sec was 0.02 mg/ml; its toxicity was also the lowest of the compounds tested with an acute LD50 of 2936 mg/kg. In rabbits, S-11 caused no local irritation to the conjunctiva or quadriceps femoris muscle at a concentration of 0.02 mg/ml. Heart, liver, kidney, spleen, lung and vagina showed no pathological changes when vaginal pessaries containing 1 or 10 mg of S-11 were administered daily, six times a week for 90 days. When vaginal pessaries of 8 or 40 mg S-11 were administered on days 7-15 after mating, no significant abnormality in general appearance, in the viscera or bone development of foetuses were found.

5-Hydroxy-2-piperidino-4,5,6,7-tetrahydroindan (5) and a number of related tetrahydro and dihydro compounds were prepared by selective mono- and dihydroxylation of the dihydro products from the Birch reduction of various alkylaminoalkylindans, tetralins, benzenes, and isoindolines. Some of these compounds showed a remarkably selective inhibition of monosynatpic spinal reflex in the segmental cat preparation.

The antipyretic effect of UP 517-03 was studied in rabbits, provided with a cannula in the lateral cerebral ventricle. Given orally as a curative treatment, UP 517-03 can abolish hyperthermic reactions induced by intracerebroventricular injection of sodium arachidonate or bacterial endotoxin. A comparison with acetylsalicylic acid and indomethacin is given. UP 517-03 does not modify the temperature of normothermic rabbits. These results suggests that the antipyretic action of UP 517-03 can be explained by an effect of this substance on the metabolism of arachidonic acid in brain.

Apomorphine (APO), 2-di-n-propylamino-4,7-dimethoxyindane (RDS-127) and 2-di-n-propylamino-5,8-dimethoxytetralin (JMC-181) were examined on a variety of biochemical and pharmacological assays to determine their possible interaction with dopamine (DA) receptors. Nanomolar concentrations of all three compounds displaced [3H]APO from specific high-affinity binding sites in rat striatal membrane preparations, while higher concentrations were required to displace [3H]spiperone or [3H]rauwolscine. APO caused a concentration-dependent increase in the ability to stimulate postsynaptic DA receptors associated with adenylate cyclase (D1-sites) in the carp retina, whereas RDS-127 or JMC-181 were inactive in concentrations up to 300 microM. APO was very active in causing contralateral turning behavior in rats with a 6-hydroxydopamine lesioned substantia nigra (SN); RDS-127 was approximately 8 times less potent in producing contralateral rotations and JMC-181 was inactive. RDS-127 produced biphasic, dose-related changes in rat spontaneous locomotor activity similar to that reported for APO. The locomotor stimulant effects of RDS-127 were 3 times more potent and 4 times greater in duration than that induced by APO. JMC-181 produced primarily sedation in the doses tested. APO, RDS-127 and JMC-181 were active in inhibiting the accumulation of dopa in the caudate nucleus and olfactory tubercle using the in vivo gamma-butyrolactone procedure; 5-hydroxytryptophan accumulations were not altered significantly. RDS-127 was 7 times more potent than APO in inhibiting dopa accumulation in the caudate nucleus and equipotent to APO in the olfactory tubercle. Dopa accumulation was weakly inhibited by JMC-181. When single unit extracellular action potentials were recorded from purported DA-containing neurons in the SN, RDS-127 decreased the firing of neurons in the pars compacta of SN (ID100 = 40 +/- 10 nmol/kg i.v.). In contrast, firing of units in the pars reticulata of SN were not altered or increased in response to RDS-127. The biochemical electrophysiological and behavioral effects of RDS-127 were blocked or reversed by DA receptor antagonists. These data indicate that RDS-127 is significantly more selective than APO in preferentially activating DA autoreceptors as opposed to the postsynaptic DA receptors in the nigrostriatal pathway. The possibilities of designing potent, long acting, nonergot, noncatechol-containing DA receptor agonists are discussed.

Racemic indacrinone is a high-ceiling, relatively long-acting diuretic. Both enantiomers have uricosuric activity, but the diuretic activity resides predominantly in the (-) enantiomer. Usual therapeutic doses of racemic indacrinone have only transient uricosuric activity, so that, as with other diuretics, hyperuricemia occurs. Sixty-five healthy men participated in a multicenter, double-blind, randomized, balanced, incomplete-block study comparing the effects on plasma urate and urate clearance of indacrinone (-) enantiomer 10 mg given concomitantly with 0, 10, 20, 40, and 80 mg (+) enantiomer (10/0, 10/10, 10/20, 10/40, 10/80), as single daily doses for 7 days. Hydrochlorothiazide (HCTZ) 50 mg daily and ticrynafen (T) 250 mg daily were controls. Each subject received two of the seven treatments, so that there were 18 subjects per treatment. On days 7 to 8, morning (mean of 0-hr values on days 7 and 8), HCTZ, 10/0, 10/10, and 10/20 elevated plasma urate by 8% to 16%. 10/40 was approximately isouricemic, and 10/80 and T lowered plasma urate by 13% and 41%. There were corresponding changes in urate clearance.