Bioorganic & Medicinal Chemistry Letters 25 (2015) 5514–5519

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Bioorganic & Medicinal Chemistry Letters

journal homepage: www.elsevier .com/ locate/bmcl

1,3-Disubstituted and 1,3,3-trisubstituted adamantyl-ureaswith isoxazole as soluble epoxide hydrolase inhibitors

http://dx.doi.org/10.1016/j.bmcl.2015.10.0660960-894X/� 2015 Elsevier Ltd. All rights reserved.

⇑ Corresponding author. Tel.: +1 530 752 7519; fax: +1 530 751 1537.E-mail address: bdhammock@ucdavis.edu (B.D. Hammock).

Vladimir Burmistrov a,b, Christophe Morisseau a, Dmitry Danilov b, Todd R. Harris a, Igor Dalinger c,Irina Vatsadze c, Tatiana Shkineva c, Gennady M. Butov b, Bruce D. Hammock a,⇑aDepartment of Entomology and Nematology, and UC Davis Comprehensive Cancer Center, University of California at Davis, One Shields Avenue, Davis, CA 95616, USAbDepartment of Chemistry, Technology and Equipment of Chemical Industry, Volzhsky Polytechnic Institute (Branch) Volgograd State Technical University, Volzhsky, RussiacN.D. Zelinsky Institute of Organic Chemistry (ZIOC) of Russian Academy of Sciences, Moscow, Russia

a r t i c l e i n f o

Article history:Received 1 August 2015Revised 19 October 2015Accepted 21 October 2015Available online 23 October 2015

Keywords:Soluble epoxide hydrolaseInhibitorAdamantaneIsocyanateUreaIsoxazole

a b s t r a c t

Adamantyl ureas are good soluble epoxide hydrolase (sEH) inhibitors; however they have limitedsolubility and rapid metabolism, thus limiting their usefulness in some therapeutic indications. Herein,we test the hypothesis that nodal substitution on the adamantane will help solubilize and stabilize thecompounds. A series of compounds containing adamantane derivatives and isoxazole functional groupswere developed. Overall, the presence of methyl on the nodal positions of adamantane yields higherwater solubility than previously reported urea-based sEH inhibitors while maintaining high inhibitionpotency. However, it did not improve microsomal stability.

� 2015 Elsevier Ltd. All rights reserved.

The mammalian soluble epoxide hydrolase (sEH, E.C. 3.3.2.10) isinvolved in the metabolism of epoxy-fatty acids to vicinal diolsthrough a catalytic addition of a water molecule.1,2 Endogenoussubstrates for the sEH include epoxides of arachidonic acid,epoxyeicosatrienoic acids (EETs), and of docosahexaenoic acid,known as EpDPEs, and other fatty acid epoxides.3,4 EETs areimportant lipid mediators that have key roles in blood pressureregulation by exerting vasodilatory effects through the activationof the Ca2+-activated K+ channels in endothelial cells, which arebeneficial in many renal and cardiovascular diseases.5,6 Further-more, the EETs and EpDPEs have some anti-inflammatory and anal-gesic properties.7 Recently, EETs have been reported to increaseefficiency of organ transplant.8 Their conversion to dihydroxye-icosatrienoic acids (DHETs) by sEH produces a molecule that isreadily conjugated and removed from the site of action. The inhibi-tion of sEH in vivo by highly selective inhibitors results in anincrease in the concentration of EETs and EpDPEs, and is accompa-nied by a reduction in angiotensin driven blood pressure, but alsoreduction of inflammation and pain, thereby suggesting that sEH isa promising target for the treatment of hypertension, inflammatorydiseases and pain.9–11

Early on, small N,N’-disubstituted symmetric ureas, such as1,3-dicyclohexyl urea, were found to be very potent inhibitors ofsEH.12–16 However, these kinds of compounds have poor solubilityin many solvents. To improve solubility, asymmetric ureas with aflexible side chain, such as AUDA (12-(3-adamantylureido)-dodecanoic acid) or AEPU (1-adamantanyl-3-{5-[2-(2-ethylethoxy)ethoxy]pentyl]}urea), were developed.17 While this class of sEHinhibitor shows biological effects when tested in vivo, they arerapidlymetabolized, limiting their utility.18 Interestingly, amajor siteof metabolism for these compounds is on the adamantine, althoughbeta oxidation of the side chains by CYPs is also important.19

Therefore, to improve the metabolic stability, a third class ofconformationally restricted inhibitors, in which the adamantinewas replaced by phenyl derivatives such as TPAU (1-trifluo-romethoxyphenyl-3-(1-acetylpiperidin-4-yl)urea) or trans-4-{4-[3-(4-trifluoromethoxyphenyl)-ureido]cyclohexyloxy} benzoic acid(t-TUCB), were designed.20,21 This latest series includes very potentand more metabolically stable sEH inhibitors that permit in vivostudies.22 However, these compounds have in general poorer solubil-ity than the corresponding adamantane containing compounds, andare expensive to synthesize since several steps (up to 5) are required.

A promising way to enhance the water solubility of the ureainhibitors of sEH is the introduction of heterocyclic moieties.23 Forexample, ureas synthesized with amino- pyridazines, pyridines,

V. Burmistrov et al. / Bioorg. Med. Chem. Lett. 25 (2015) 5514–5519 5515

pyrimidines, triazines, oxazoles and thiazoles containing aminogroups showed high potency against epoxide hydrolases fromMycobacterium tuberculosis.24 Thus, here as a continuation of previ-ous work25,26 we report the testing of adamantyl-ureas containingisoxazoles, howeverwe also tested the hypothesis that nodal substi-tution on the adamantane will help solubilize and stabilize theresulting compounds because for adamantane containing ureainhibitors hydroxylation of nodal carbon is important metabolicpathway leading to a decrease of inhibitory potency.

Ureas were synthesized from 1-(isocyanatomethyl)adamantane(1a) or 1-isocyanato-3,5-dimethyladamantane (1b) and 3,5-disub-stituted isoxazoles with aminomethyl or pyrrolidine-2-yl as one ofthe substituents. Compound 1a was selected due to the flexibility-giving methyl spacer. The starting isoxazoles also contain a methy-lene bridge between the amino group and the isoxazole ring, insome cases this bridge included the pyrrolidine ring. Selectedisoxazoles contain electron donor (Me, Et, i-Pr) as well as electronacceptor (4-MeC6H4, 4-MeOC6H4, 3(4)-FC6H4) substituents andamino methyl groups in the 3 and 5 positions.27–33 Such a seriesof disubstituted isoxazoles will allow us to investigate theinfluence of its structure on the urea formation reaction and onthe inhibition potency of corresponding ureas.

As described in Scheme 1, simple (one step) and complemen-tary approaches were used to obtain the desired compounds inhigh yield (>95%).

The inhibition potency of the synthesized compounds wasmeasured using recombinant purified human sEH and CMNPC(cyano(6-methoxynaphthalen-2-yl)methyl((3-phenyloxiran-2-yl)methyl)carbonate) as a substrate as described.34 For the isoxazolecontaining 1,3-disubstituted ureas, the best inhibitory potency(4.9 nM) was recorded for the compound 3c with furyl group in5th position of isoxazole ring (Table 1). Compound 3d with themethyl substituent in 5th position of isoxazole ring has good inhi-bition potency (6.7 nM). Further increase of this substituent to theethyl (3e) and i-propyl (3f) leads to the 30- and 45-fold decrease inpotency (higher IC50) and accompanied decrease in water solubil-ity. Potency of the ureas with phenyl substituents in 5th position

NCON

O R

H2N

2-3a R = CH3

2-3b R = O CH3

2-3c R =O

1a 2a-c

a

NCON

O

R

H2N

2-3d R = CH3

2-3e R = -CH2-CH3

F2-3f R = -CH(CH 3)2

2-3g R =

1a 2d-h

F

2-3h R =

Scheme 1. Reagents and cond

of isoxazole ring is only slightly affected by the structure of thosegroups and ranges from 10.5 to 16.6 nM.

Due to the low reactivity of secondary amines in the reaction ofnucleophilic addition to isocyanates reactions of isoxazoles 2i–mwere carried out at 80 �C in presence of Et3N (Scheme 2).

Potency of 1,3,3-trisubstituted ureas clearly shows thatavailability of both NH in the urea group is vital for the satisfactoryinhibition of sEH. Disruption of the ability to create one hydrogenbond leads to an up to significant decrease in activity in somecases. For example compound 3k is >5-fold less active than thecorresponding 1,3-disubstituted urea 3f. Ureas synthesized fromisoxazole with aminomethyl group in 3rd position are more potent(up to 5-fold) than those with the amino methyl group in the 5thposition. Probably this is due to the formation of the additionalhydrogen bonds. The hydrogen bond acceptor in ureas synthesizedfrom 5-amino isoxazoles is probably not able to reach thenecessary distance to create such a bond (Scheme 3).

While 1,3-disustituted ureas containing the adamantanemoiety were widely investigated as soluble epoxide hydrolaseinhibitors only 1-isocyanato adamantane was used for theirformation. Introduction of methyl groups into nodal positions ofadamantane significantly lowers melting point of the derivatives.Moreover, the metabolism of adamantyl-containing 1,3-disubsti-tuted ureas in vivo proceeds through the hydroxylation of nodalpositions and the corresponding hydroxy derivatives have up to50 fold less inhibitory activity.23 In this case we decided to synthe-size sEH inhibitor from 1-isocyanato-3,5-dimethyladamantane(1b).24 The boiling point of compound 1b (93 �C at 10 Torr)36 islower than that of compound 1a (98 �C at 10 Torr)36 so weassumed a corresponding reduction of melting points would occurwith the appropriate 1,3-disubstituted ureas (Table 3).

For the compounds 4a–4c and 4g the replacement of theadamantane part of the molecule did not result in noticeablechange of the inhibitory potency. Surprisingly, compound 4d is10-fold less potent than 3d, which is the second-best inhibitor ofthis series. However, we have mentioned the tendency of eachnew methyl group introduced into the aliphatic substituent in

HN

HN

O

NO

R

3a-c

HN

HN

O

ON

R

3d-h

a

itions: (a) DMF, rt, 12 h.

Table 1IC50 values for the isoxazole 1,3-disubstituted urea-based sEH inhibitors 3a–h

# Structure IC50a (nM) Solubilityb (lM) Mp (�C)

3aHN

HN

O

NO

CH3

15.4 75 < S < 100 198–199

3bHN

HN

O

NO

O CH3

12.9 100 < S < 125 180–181

3cHN

HN

O

NO

O

4.9 75 < S < 100 174–175

3d HN

HN

O

ON

CH3

6.7 450 < S < 475 135–137

3e HN

HN

O

ON 29.4 300 < S < 325 120–121

3f HN

HN

O

ON 44.6 125 < S < 150 108–109

3gHN

HN

O

ON

F

16.6 75 < S < 100 160–161

3h

HN

HN

O

ON

F

10.5 50 < S < 75 186–187

a As determined via a kinetic fluorescent assay.34,35b Solubilities were measured in sodium phosphate buffer (pH 7.4, 0.1 M) containing 1% of DMSO.

5516 V. Burmistrov et al. / Bioorg. Med. Chem. Lett. 25 (2015) 5514–5519

5th position of isoxazole to reduce potency. In this case, we canconclude that the additional methyl groups for this series of ureascaused a decrease in the inhibitory activity as well as watersolubility (comparing data in Tables 1 and 2). But presence of thephenyl or furyl rings negate this effect. Introduction of isocyanate1b instead of 1a leads to the reduction of melting points ofcorresponding ureas at about 10 �C but additional methyl groups

generally result in 2-fold decreased water solubility. Decreasedwater solubility is correlated with cLogP (Table 4).

To further assess the properties of the compounds, wemeasured their stability in human liver microsomes (Table 4).

However contrary to our assumption introduction of methylgroups to the nodal positions of adamantane did not improvemicrosomal stability of the corresponding ureas. This effect was

1a

ON

RHN

2j,k

3j,k

N O

NH i-Pr

Me

2i HN N N

O

i-Pr

O

Me

3i

Et3N, DMF

80 °C, 12h

j R = Me, k R = i-Pr

NO

i-PrNHMe

2l HN N O

N

i-Pr

O

Me

3l

NO

MeHN

2mHN O

NO

N

Me

3m

HN O

NN

O

R

NCO

Scheme 2. Synthesis of 1,3,3-trisubstituted ureas with isoxazole part.

1b

2g

2d

4d

a

a R = CH3, b R = -O-CH3

2a, 2b

4a, 4b

2c

4c

NCO

4g

NH

NH

O

N O O

NH

NH

O

N O

R

NH

NH

O

O NF

NH

NH

O

O NCH3

Scheme 3. Reagents and conditions: (a) DMF, rt, 12 h.

V. Burmistrov et al. / Bioorg. Med. Chem. Lett. 25 (2015) 5514–5519 5517

observed probably due to the rapid metabolism of isoxazole ring,although isolated methyl groups often are rapidly oxidized byCYP enzymes.

We describe the synthesis and structure–activity relationshipof a series of adamantyl-ureas with isoxazole ring containingvarious substituents. Some ureas have methyl groups in nodalpositions of adamantane. The data show that such ureas showvery good inhibition potency along with high water solubility

(compared to previously reported urea-based sEH inhibitors).We showed that both NH in urea group are essential for theinhibitor binding on the active site of sEH. Introduction ofmethyl groups to the nodal positions of the adamantane did notaffect inhibition potency (which indicates that there is stillsufficient space in the cavity of the enzyme) as long as notaffect microsomal stability but lead to the reduction of watersolubility.

Table 2IC50 values for the isoxazole 1,3,3-trisubstituted urea-based sEH inhibitors 3i–m

# IC50a (nM) Solubilityb (lM) Mp (�C)

3i HN N N

O

O

Me575.8 200 < S < 225 119–120

3j

HN O

NN

O

CH3524.3 525 < S < 550 176–177

3k

HN O

NN

O247.2 250 < S < 275 128–129

3l HN N O

N

O

Me190.6 350 < S < 375 146–148

3m

HN O

NO

N

CH391.0 575 < S < 600 157–158

a As determined via a kinetic fluorescent assay.34,35b Solubility was measured in sodium phosphate buffer (pH 7.4, 0.1 M) containing 1% of DMSO.

Table 3IC50 values for the isoxazole 1,3-disubstituted urea-based sEH inhibitors with 1,3-dimethyladamantane moiety 4a–d and 4g

# IC50a (nM) Solubilityb (lM) Mp (�C)

4a 25.8 125 < S < 150 185–1864b 15.0 25 < S < 50 189–1904c 4.1 75 < S < 100 149–1504d 123.0 200 < S < 225 130–1314g 17.0 75 < S < 100 146–147

aAs determined via a kinetic fluorescent assay.34,35

bSolubilities were measured in sodium phosphate buffer (pH 7.4, 0.1 M) containing 1% of DMSO.

5518 V. Burmistrov et al. / Bioorg. Med. Chem. Lett. 25 (2015) 5514–5519

Table 4IC50, water solubility and microsomal stability of selected compounds

# IC50 nMa Solubilityb (lM) cLogPc Microsomal stabilityd

(%)NADPH

� +

3a 15.6 ± 0.7 75 < S < 100 4.24 97 ± 4 0.4 ± 0.24a 28.8 ± 4.5 125 < S < 150 4.50 115 ± 11 0.4 ± 0.23b 12.5 ± 1.8 100 < S < 125 3.85 87 ± 6 0.8 ± 0.24b 18.0 ± 2.9 25 < S < 50 3.89 102 ± 11 0.4 ± 0.33c 4.9 ± 0.1 75 < S < 100 2.59 91 ± 8 0.4 ± 0.14c 4.8 ± 0.6 75 < S < 100 2.63 95 ± 1 0.3 ± 0.13d 9.9 ± 2.9 450 < S < 475 2.36 72 ± 4 2.9 ± 0.54d 111.1 ± 10.3 200 < S < 225 2.62 83 ± 3 0.1 ± 0.13g 13.7 ± 3.0 75 < S < 100 3.91 97 ± 10 0.3 ± 0.14g 14.2 ± 2.5 75 < S < 100 4.17 92 ± 6 0.4 ± 0.1

a As determined via a kinetic fluorescent assay.34,35 Results are average ± stan-dard deviation of three separate measurement.

b Solubility was measured in sodium phosphate buffer (pH 7.4, 0.1 M) containing1% of DMSO.

c Calculated using ChemBioDraw Ultra v12.0 (PerkinElmer, Waltham, MA).d Percent of compound (1 lM) remaining after 30 min incubation with human

liver microsomes (1 mg/mL) at 37 �C with or without NADPH generating system.Results are the average of triplicates ± standard deviation.

V. Burmistrov et al. / Bioorg. Med. Chem. Lett. 25 (2015) 5514–5519 5519

Acknowledgements

The reported study was partially funded by Council for Grantsunder the President of the Russian Federation (program of statesupport for young PhDs, project MK-5809.2015.3), NationalInstitute of Environmental Health Sciences (NIEHS) Grant R01ES002710, and NIEHS Superfund Research Program Grant P42ES004699.

Supplementary data

Supplementary data associated with this article can be found, inthe online version, at http://dx.doi.org/10.1016/j.bmcl.2015.10.066.

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1,3-Disubstituted and 1,3,3-trisubstituted adamantyl-ureas with isoxazole as soluble

epoxide hydrolase inhibitors

Vladimir Burmistrovb, Christophe Morisseaua, Dmitry Danilovb, Todd R. Harrisa, Igor

Dalingerc, Irina Vaczadzec, Tatiana Shkinevac, Gennady M. Butovb,c and Bruce D.

Hammocka*

a Department of Entomology and Comprehensive Cancer Center, University of California,

Davis, CA, 95616, USA

b Department of Chemistry, Technology and Equipment of Chemical Industry, Volzhsky

Polytechnic Institute (branch) Volgograd State Technical University, Volzhsky, Russia

c N.D. Zelinsky Institute of Organic Chemistry (ZIOC) of Russian Academy of Sciences,

Moscow, Russia

* To whom correspondence should be addressed: Bruce D. Hammock, Department of

Entomology, University of California at Davis, One Shields Avenue, Davis, CA 95616. Tel:

530 752 7519; Fax: 530-751-1537; E-mail: bdhammock@ucdavis.edu

Synthetic procedures General. 1-(Isocyanatomethyl)adamantane (1a) or 1-isocyanato-3,5-dimethyladamantane (1b) were obtained following the published procedure.1 Isoxazoles 2a-c,e-m were synthesized using known methods.2-8 Isoxazole 2d and other reagents and solvents were obtained from commercial suppliers and were used without further purification. All reactions, unless otherwise described, were performed under an inert atmosphere of dry nitrogen. IR spectra were registered on a Bruker Alpha spectrometer in KBr pellets. 1H and 13C NMR spectra were acquired on a Bruker AM300 (300 and 75 MHz, respectively) spectrometer in DMSO-d6, with TMS as internal standard. Mass spectra were recorded on a Hewlett Packard GC 5890 Series II / MSD 5972 GC-MS system (EI ionization, 70 eV, mass selective detector). Elemental analysis was performed on a Perkin Elmer Series II 2400 Elemental Analyzer. Melting points were determined on a Boetius heating bench and are uncorrected. General Procedure for the synthesis of 1,3-Disubstituted Ureas 3a-h, 4a-d and 4g. Corresponding aminomethylisoxazole 2a-h (1 mmol) was added to a solution of compound 1a (191 mg, 1 mmol for compounds 3a-h) or compound 1b (205 mg, 1 mmol for compounds 4a-d and 4g) in DMF (5 ml) at 0°С. The reaction mixtures were allowed to slowly warm to room temperature overnight. The reaction mixtures were poured into water, and the resulting precipitates were collected and washed with 1 N HCl solution followed by water. The crude product was purified by silica gel chromatography. 1-(Adamant-1-ylmethyl)-3-{[5-(4-methylphenyl)isoxazol-3-yl]methyl}urea (3a). The general method above was used with [5-(4-methylphenyl)isoxazol-3-yl]methylamine (2a) to afford a white solid (298 mg, 79% yield). Mp 198-199 °С. IR spectrum, ν, cm-1: 1631 (С=O), 3339 (N–H). 1Н NMR spectrum, δ, ppm (J, Hz): 7.71 (2H, d, J = 7.9, H-2,6 Ar); 7.32 (2H, d, J = 7.8, H-3,5 Ar); 6.76 (1H, s, H-4 Iz*); 6.33 (1H, t, J = 5.5, NH); 6.00 (1Н, t, J = 5.8, NH); 4.28 (2H, d, J = 5.7, NHCH2Iz); 2.74 (2H, d, J = 5.9, AdCH2NH); 2.35 (3Н, s, CH3); 1.91 (3Н, br. s, 3CH Ad); 1.72-1.38 (6Н, m, 3CH2 Ad); 1.41 (6H, s, 3CH2 Ad). 13C NMR spectrum, δ, ppm: 168.9 (С-5 Iz); 163.9 (С-3 Iz); 158.2 (СО); 140.2 (C Ar); 129.7 (CH Ar); 125.4 (CH Ar); 124.2 (C Ar); 98.9 (С-4 Iz); 51.1 (NHCH2Iz); 39.7 (2,8,9-CН2 Ad); 36.6 (4,6,10- CН2 Ad); 35.3 (AdCH2NH); 33.4 (C-1 Ad); 27.7 (3,5,7-СH Ad); 20.9 (CH3). MS (ESI) m/z: 379 (5%, [M]+), 135 (100%, [Ad]+). Anal. (C23H29N3O2) C 72.66%, H 7.80%, N 11.00%. 1-(Adamant-1-ylmethyl)-3-{[5-(4-methoxyphenyl)isoxazol-3-yl]methyl}urea (3b). The general method above was used with [5-(4-methoxyphenyl)isoxazol-3-yl]methylamine (2b) to afford a white solid (330 mg, 83% yield). Mp 180-181 °С. IR spectrum, ν, cm-1: 1635 (С=O), 2846 (Ar–O–CH3), 3356 (N–H). 1H NMR spectrum, δ, ppm (J, Hz): 7.76 (2H, d, J = 8.6, H-2,6 Ar); 7.06 (2H, d, J = 8.6, H-3,5 Ar); 6.69 (1H, s, H-4 Iz); 6.33 (1H, t, J = 5.7, NH); 6.00 (1Н, t, J = 6.0, NH); 4.27 (2H, d, J = 5.8, NHCH2Iz); 3.82 (3H, s, OCH3); 2.74 (2H, d, J = 6.0, AdCH2NH); 1.92 (3Н, br. s, 3CH Ad); 1.72-1.38 (6Н, m, 3CH2 Ad); 1.41 (6H, s, 3CH2 Ad). 13C NMR spectrum, δ, ppm: 168.8 (С-5 Iz); 163.8 (С-3 Iz); 160.7 (C Ar); 158.2 (СО); 127.1 (CH Ar); 119.6 (C Ar); 114.6 (CH Ar); 98.0 (С-4 Iz); 55.3 (OCH3); 51.1 (NHCH2Iz); 39.7 (2,8,9-CН2 Ad); 36.6 (4,6,10-CН2 Ad); 35.3 (AdCH2NH); 33.4 (C-1 Ad); 27.7 (3,5,7-СH Ad). MS (ESI) m/z: 395 (5%, [M]+), 135 (100%, [Ad]+). Anal. (C23H29N3O3) C 69.82%, H 7.50%, N 10.59%. 1-(Adamant-1-ylmethyl)-3-{[5-(furan-2-yl)isoxazol-3-yl]methyl}urea (3c). The general method above was used with [5-(furan-2-yl)isoxazol-3-yl]methylamine (2c) to afford a white

solid (320 mg, 90% yield). Mp 174-175 °С. IR spectrum, ν, cm-1: 1628 (С=O), 3359 (N–H). 1H NMR spectrum, δ, ppm (J, Hz): 7.92 (1H, s, H Fur); 7.12 (1H, d, J = 3.3, H Fur); 6.71 (1H, s, H Fur); 6.59 (1H, s, H-4 Iz); 6.35 (1H, t, J = 5.5, NH); 6.03 (1Н, t, J = 5.7, NH,); 4.28 (2H, d, J = 5.6, NHCH2Iz); 2.74 (2H, d, J = 5.9, AdCH2NH); 1.92 (3Н, br. s, 3CH Ad); 1.72-1.38 (6Н, m, 3CH2 Ad); 1.41 (6H, s, 3CH2 Ad). 13C NMR spectrum, δ, ppm: 163.7 (С-5 Iz); 160.4 (С-3 Iz); 158.2 (СО); 145.3 (CH Fur); 142.2 (C Fur); 112.3 (CH Fur); 110.9 (CH Fur); 98.8 (С-4 Iz); 51.1 (NHCH2Iz); 39.8 (2,8,9-CН2 Ad); 36.6 (4,6,10-CН2 Ad); 35.1 (AdCH2NH); 33.5 (C-1 Ad); 27.7 (3,5,7-СH Ad). MS (ESI) m/z: 355 (7%, [M]+), 135 (100%, [Ad]+). Anal. (C20H25N3O3) C 67.41%, H 6.98%, N 11.94%. 1-(Adamant-1-ylmethyl)-3-[(3-methylisoxazol-5-yl)methyl]urea (3d). The general method above was used with (3-methylisoxazol-5-yl)methylamine (2d) to afford a white solid (257 mg, 85% yield). Mp 135-137 °С. IR spectrum, ν, cm-1: 1630 (С=O), 3344 (N–H). 1H NMR spectrum, δ, ppm (J, Hz): 6.28 (1H, br. s, NH); 6.07 (1H, s, H-4 Iz); 5.88 (1H, br. s, NH); 4.29 (2H, d, J = 5.7, NHCH2Iz); 2.72 (2H, d, J = 5.8, AdCH2NH); 2.19 (3Н, s, CH3); 1.93 (3Н, br. s, 3CH Ad); 1.74-1.40 (6Н, m, 3CH2 Ad); 1.42 (6H, s, 3CH2 Ad). 13C NMR spectrum, δ, ppm: 171.4 (С-5 Iz); 159.3 (С-3 Iz); 157.9 (СО); 101.9 (С-4 Iz); 51.1 (NHCH2Iz); 39.7 (2,8,9-CН2 Ad); 36.6 (4,6,10-CН2 Ad); 35.4 (AdCH2NH); 33.4 (C-1 Ad); 27.7 (3,5,7-СH Ad); 10.9 (CH3). MS (ESI) m/z: 303 (8%, [M]+), 135 (100%, [Ad]+). Anal. (C17H25N3O2) C 67.19%, H 8.38%, N 13.97%. 1-(Adamant-1-ylmethyl)-3-[(3-ethylisoxazol-5-yl)methyl]urea (3e). The general method above was used with (3-ethyl-isoxazol-5-yl)methylamine (2e) to afford a white solid (250 mg, 79% yield). Mp 120-121 °С. IR spectrum, ν, cm-1: 1630 (С=O), 3361 (N–H). 1H NMR spectrum, δ, ppm (J, Hz): 6.33 (1H, t, J = 5.5, NH); 6.13 (1H, s, H-4 Iz); 5.99 (1Н, t, J = 5.7, NH); 4.28 (2H, d, J = 5.1, NHCH2Iz); 2.72 (2H, d, J = 5.8, AdCH2NH); 2.58 (2Н, q, J = 7.2, СН2CH3); 1.92 (3Н, br. s, 3CH Ad); 1.72-1.38 (6Н, m, 3CH2 Ad); 1.41 (6H, s, 3CH2 Ad); 1.16 (3Н, t, J = 10.5, СН2СН3).

13C NMR spectrum, δ, ppm: 171.4 (С-5 Iz); 164.6 (С-3 Iz); 158.0 (СО); 100.6 (С-4 Iz); 51.1 (NHCH2Iz); 39.8 (2,8,9-CН2 Ad); 36.6 (4,6,10-CН2 Ad); 35.5 (AdCH2NH); 33.5 (C-1 Ad); 27.7 (3,5,7-СH Ad); 18.8 (СН2CH3); 12.47 (CH2CH3). MS (ESI) m/z: 317 (7%, [M]+), 135 (100%, [Ad]+). Anal. (C18H27N3O2) C 68.28%, H 8.58%, N 12.98%. 1-(Adamant-1-ylmethyl)-3-[(3-isopropylisoxazol-5-yl)methyl]urea (3f). The general method above was used with (3-isopropylisoxazol-5-yl)methylamine (2f) to afford a white solid (300 mg, 91% yield). Mp 108-109 °С. IR spectrum, ν, cm-1: 1633 (С=O), 3342 (N–H). 1H NMR spectrum, δ, ppm (J, Hz): 6.33 (1H, t, J = 5.7, NH); 6.16 (1H, s, H-4 Iz); 5.98 (1Н, J = 5.8, NH); 4.29 (2H, d, J = 5.8, NHCH2Iz); 3.08-2.87 (1Н, m, СНМе2); 2.73 (2H, d, J = 6.0, AdCH2NH); 1.92 (3Н, br. s, 3CH Ad); 1.72-1.38 (6Н, m, 3CH2 Ad); 1.40 (6H, s, 3CH2 Ad); 1.19 (6Н, d, J = 6.0, CH(CH3)2).

13C NMR spectrum, δ, ppm: 171.4 (С-5 Iz); 168.7 (С-3 Iz); 158.0 (СО); 99.3 (С-4 Iz); 51.1 (NHCH2Iz); 39.8 (2,8,9-CН2 Ad); 36.6 (4,6,10-CН2 Ad); 35.6 (AdCH2NH); 33.6 (C-1 Ad); 27.8 (3,5,7-СH Ad); 25.9 (СНМе2); 21.5 (CH(CH3)2). MS (ESI) m/z: 331 (7%, [M]+), 135 (100%, [Ad]+). Anal. (C19H29N3O2) C 68.73%, H 8.91%, N 12.61%. 1-(Adamant-1-ylmethyl)-3-{[3-(3-fluorophenyl)isoxazol-5-yl]methyl}urea (3g). The general method above was used with [3-(3-fluorophenyl)isoxazol-5-yl]methylamine (2g) to afford a white solid (333 mg, 87% yield). Mp 160-161 °С. IR spectrum, ν, cm-1: 1632 (С=O), 3333 (N–H). 1H NMR spectrum, δ, ppm (J, Hz): 7.77-7.59 (2H, m, H-2,5 Ar); 7.56 (1H, q, J = 7.5, H-6 Ar); 7.34 (1Н, t, J = 7.5, H-4 Ar); 6.85 (1H, s, H-4 Iz); 6.43 (1H, t, J = 5.8, NH);

6.04 (1Н, t, J = 5.9, NH); 4.40 (2H, d, J = 5.9, NHCH2Iz); 2.74 (2H, d, J = 6.0, AdCH2NH); 1.92 (3Н, br. s, 3CH Ad); 1.72-1.38 (6Н, m, 3CH2 Ad); 1.41 (6H, s, 3CH2 Ad). 13C NMR spectrum, δ, ppm (J, Hz): 173.0 (С-5 Iz); 162.4 (d, 1JC–F = 244.0, C–F); 160.8 (С-3 Iz); 158.0 (СО); 131.2 (d, 3JC–F = 8.4, 5-CH Ar); 130.9 (d, 3JC–F = 8.4, C-1 Ar); 122.6 (d, 4JC–F = 2.8, 6-CH Ar); 116.9 (d, 2JC–F = 21.0, CH Ar); 113.3 (d, 2JC–F = 23.0, CH Ar); 99.6 (С-4 Iz); 51.1 (NHCH2Iz); 39.7 (2,8,9-CН2 Ad); 36.6 (4,6,10-CН2 Ad); 35.6 (AdCH2NH); 33.5 (C-1 Ad); 27.7 (3,5,7-СH Ad). MS (ESI) m/z: 383 (9%, [M]+), 135 (100%, [Ad]+). Anal. (C22H26FN3O2) C 68.86%, H 6.91%, N 10.96%. 1-(Adamant-1-ylmethyl)-3-{[3-(4-fluorophenyl)isoxazol-5-yl]methyl}urea (3h). The general method above was used with [3-(4-fluorophenyl)isoxazol-5-yl]methylamine (2h) to afford a white solid (325 mg, 85% yield). Mp 186-187 °С. IR spectrum, ν, cm-1: 1632 (С=O), 3354 (N–H). 1H NMR spectrum, δ, ppm (J, Hz): 7.98-7.82 (2H, m, H-2,6 Ar); 7.34 (2H, t, J = 8.7, H-3,5 Ar); 6.78 (1H, s, H-4 Iz); 6.44 (1H, br. s, NH); 6.05 (1Н, t, J = 5.1, NH); 4.39 (2H, d, J = 4.7, NHCH2Iz); 2.73 (2H, d, J = 5.2, AdCH2NH); 1.92 (3Н, br. s, 3CH Ad); 1.72-1.38 (6Н, m, 3CH2 Ad); 1.41 (6H, s, 3CH2 Ad). 13C NMR spectrum, δ, ppm (J, Hz): 172.8 (С-5 Iz); 162.8 (d, 1JC–F = 248.4, C–F); 161.5 (С-3 Iz); 158.0 (СО); 128.8 (d, 3JC–F = 8.6, 2,6-CH Ar); 125.2 (d, 4JC–F = 3.1, C-1 Ar); 116.1 (d, 2JC–F = 21.8, 3,5-CH Ar); 99.4 (С-4 Iz); 51.1 (NHCH2Iz); 39.8 (2,8,9-CН2 Ad); 36.6 (4,6,10-CН2 Ad); 35.6 (AdCH2NH); 33.4 (C-1 Ad); 27.7 (3,5,7-СH Ad). MS (ESI) m/z: 383 (10%, [M]+), 135 (100%, [Ad]+). Anal. (C22H26FN3O2) C 68.87%, H 6.77%, N 11.02%. 1-(3,5-Dimethyladamant-1-yl)-3-{[5-(4-methylphenyl)isoxazol-3-yl]methyl} urea (4a). The general method above was used with [5-(4-methoxyphenyl)isoxazol-3-yl]methylamine (2a) to afford a white solid (357 mg, 93% yield). Mp 185-186 °С. 1H NMR spectrum (DMSO-d6), δ, ppm (J, Hz): 7.72 (2H, d, J = 7.9, CHPh); 7.34 (2H, d, J = 7.9, CHPh); 6.75 (1H, s, 4-H Iz); 6.18 (1H, t, J = 5.4, NHCH2); 5.75 (1Н, s, NH); 4.22 (2H, d, J = 5.5, NHCH2); 2.36 (3Н, s, Ме); 2.06 (1Н, br. s, CH Ad); 1.71 (2Н, s, CH2 Ad); 1.57-1.48 (4Н, m, CH2 Ad); 1.32-1.21 (4H, m, CH2 Ad); 1.09 (2Н, s, CH2 Ad); 0.81 (6Н, s, Ме). 13C NMR spectrum, (DMSO-d6), δ, ppm: 168.92 (5-С Iz); 163.81 (3-С Iz); 156.75 (СО); 140.14 (CPh); 129.74 (CHPh); 125.43 (CHPh); 124.23 (CPh); 98.86 (4-С Iz); 53.09; 51.23 (NCH2); 50.31; 49.06; 47.99; 45.60; 42.35; 41.09; 40.37; 34.86; 31.86; 30.06; 29.59; 20.94 (Me). Anal. (C24H31N3O2) C 73.21%, H 7.99%, N 10.63%. 1-(3,5-Dimethyladamant-1-yl)-3-{[5-(4-metoxypfenyl)isoxazol-3-yl]methyl}urea (4b). The general method above was used with [5-(4-methoxyphenyl)isoxazol-3-yl]methylamine (2b) to afford a white solid (347 mg, 85% yield). Mp 189-190 °С. 1H NMR spectrum (DMSO-d6), δ, ppm (J, Hz): 7.78 (2H, d, J = 8.7, CHPh,); 7.08 (2H, d, J = 8.7, CHPh); 6.67 (1H, s, 4-H Iz); 6.17 (1H, t, J = 5.7, NH); 5.74 (1Н, s, NH); 4.21 (2H, d, J = 5.8, CH2); 3.82 (3H, s, OMe); 2.09 (3Н, br. s, CH, CH2 Ad); 1.72 (2Н, s, CH2 Ad); 1.55-1.48 (3Н, m, CH2 Ad); 1.32-1.21 (3H, m, CH2 Ad); 1.09 (2Н, s, CH2 Ad); 0.81 (6Н, s, Ме). 13C NMR spectrum, (DMSO-d6), δ, ppm: 168.81 (5-С Iz); 163.72 (3-С Iz); 160.71 (CPh); 156.73 (СО); 127.17 (CHPh); 119.58 (CPh); 114.60 (CHPh); 97.96 (4-С Iz); 55.31 (OMe); 51.21 (NCH2); 50.30; 47.98; 42.34; 41.08; 40.36; 34.84; 31.85; 30.04; 29.58. Anal. (C24H31N3O3) C 70.33%, H 7.62%, N 10.29%. 1-(3,5-Dimethyladamant-1-yl)-3-{[5-(furan-2-yl)isoxazol-3-yl]methyl}urea (4c). The general method above was used with [5-(furan-2-yl)isoxazol-3-yl]methylamine (2c) to afford a white solid (328 mg, 89% yield). Mp 149-150 °С. 1H NMR spectrum (DMSO-d6), δ, ppm (J, Hz): 7.92 (1H, s, CH Fur); 7.12 (1H, d, J = 3.4, CH Fur); 6.62 (1H, br. s, CH Fur); 6.57

(1H, s, 4-H Iz); 6.19 (1H, t, J = 5.6, NH); 4.22 (2H, d, J = 5.8, CH2); 2.09 (3Н, br. s, CH, CH2 Ad); 1.70 (2Н, s, CH2 Ad); 1.55-1.48 (3Н, m, CH2 Ad); 1.30-1.23 (3H, m, CH2 Ad); 1.09 (2Н, s, CH2 Ad); 0.81 (6Н, s, Ме). 13C NMR spectrum, (DMSO-d6), δ, ppm: 163.72 (5-С Iz); 160.42 (3-С Iz); 156.76 (СО); 145.30 (CH Fur); 142.24 (C Fur); 112.28 (CH Fur); 110.97 (CH Fur); 98.76 (4-С Iz); 51.24 (NCH2); 50.30; 47.96; 42.34; 40.35; 34.67; 31.87; 30.06; 29.58. Anal. (C21H27N3O3) C 68.22%, H 7.32%, N 11.33%.

1-(3,5-Dimethyladamant-1-yl)-3-[(3-methylisoxazol-5-yl)methyl]-urea (4d). The general method above was used with (3-methylisoxazol-5-yl)methylamine (2d) to afford a white solid (285 mg, 90% yield). Mp 130-131°С. 1H NMR spectrum (DMSO-d6), δ, ppm (J, Hz): 6.17 (1H, t, J = 5.9, NHCH2); 6.06 (1H, s, 4-H Iz); 5.74 (1H, s, NH); 4.22 (2H, d, J = 5.9, NHCH2); 2.19 (3Н, s, Ме); 2.05 (1Н, br. s, CH Ad); 1.73 (2Н, s, CH2 Ad); 1.55-1.46 (4Н, m, CH2 Ad); 1.31-1.21 (4H, m, CH2 Ad); 1.08 (2Н, s, CH2 Ad); 0.80 (6Н, s, Ме). 13C NMR spectrum, (DMSO-d6), δ, ppm: 171.36 (5-С Iz); 159.28 (3-С Iz); 156.45 (СО); 101.86 (4-С Iz); 53.09; 51.21 (NCH2); 50.29; 49.06; 47.94; 45.60; 42.33; 41.09; 40.34; 34.90; 31.85; 30.04; 29.56; 10.86 (Me). Anal. (C18H27N3O2) C 68.10%, H 8.51%, N 13.20%.

1-(3,5-Dimethyladamant-1-yl)-3-{[3-(3-fluorophenyl)isoxazol-5-yl]methyl}urea (4g). The general method above was used with [3-(3-fluorophenyl)isoxazol-5-yl]methylamine (2g) to afford a white solid (349 mg, 88% yield). Mp 146-147°С. 1H NMR spectrum (DMSO-d6), δ, ppm (J, Hz): 7.70 (2H, m, CHPh); 7.55 (1H, q, J = 7.3, CHPh); 7.33 (1Н, t, J = 7.3); 6.83 (1H, s, 4-H isoxazol); 6.28 (1H, t, J = 5.8, NH); 5.78 (1Н, s, NH); 4.34 (2H, d, J = 5.9, CH2); 2.09 (3Н, br. s, CH, CH2 Ad); 1.71 (2Н, s, CH2 Ad); 1.55-1.49 (3Н, m, CH2 Ad); 1.31-1.22 (3H, m, CH2 Ad); 1.09 (2Н, s, CH2 Ad); 0.80 (6Н, s, Ме). 13C NMR spectrum, (DMSO-d6), δ, ppm: 173.01 (5-С ); 162.44 (d, CF, 1J = 238.78 Hz); 160.8 (3-С Iz); 156.51 (СО); 131.24 (d, 5-CH, 3JCF = 8.38 Hz); 130.86 (d, 1-C, 3JCF = 8.51 Hz); 122.68 (d, 6-CH, 4JCF = 2.74 Hz); 116.94 (d, CH, 2JCF = 21.06 Hz); 113.34 (d, CH, 2JCF = 23.11 Hz); 99.60 (4-С Iz); 53.09; 51.29 (NCH2); 50.30; 47.95; 42.34; 40.35; 35.07; 31.87; 30.06; 29.58. Anal. (C23H28FN3O2) C 69.54%, H 7.12%, N 10.55%.

General Procedure for the synthesis of 1,3,3-Trisubstituted Ureas 3i-m. Corresponding 3,5-R1,R2-isoxazole 2i-m (1 mmol) and Et3N (0.14 ml, 1 mmol) were added to a solution of compound 1a (191 mg, 1 mmol) in DMF (5 ml) at room temperature. The mixture was kept at 80°С for 12 h. The reaction mixtures were poured into water, and the resulting precipitates were collected and washed with 1 N HCl solution followed by water. The crude product was purified by silica gel chromatography. 1-(Adamant-1-ylmethyl)-3-[(5-isopropylisoxazol-3-yl)methyl]-3-methylurea (3i). The general method above was used with N-methyl-(5-isopropylisoxazol-3-yl)methylamine (2i) to afford a white solid (210 mg, 61% yield). Mp 119-120 °С. IR spectrum, ν, cm-1: 1631 (С=O), 3376 (N–H). 1H NMR spectrum, δ, ppm (J, Hz): 6.20 (1H, t, J = 5.6, NH); 6.02 (1H, s, H-4 Iz); 4.41 (2H, s, NCH2Iz); 3.14-2.92 (1Н, m, СНМе2); 2.82 (3Н, s, NCH3); 2.78 (2H, d, J = 6.0, AdCH2NH); 1.90 (3Н, br. s, 3CH Ad); 1.67-1.52 (6Н, m, 3CH2 Ad); 1.39 (6H, s, 3CH2 Ad); 1.22 (6Н, d, J = 6.0, CH(CH3)2).

13C NMR spectrum, δ, ppm: 178.1 (С-5 Iz); 161.3 (С-3 Iz); 158.0 (СО); 98.4 (С-4 Iz); 51.5 (NCH2Iz); 43.5 (NCH3); 39.9 (2,8,9-CН2 Ad); 36.6 (4,6,10-CН2 Ad); 34.4 (AdCH2NH); 34.0 (C-1 Ad); 27.9 (3,5,7-СH Ad); 26.4 (СНМе2); 20.6 (CH(CH3)2). MS (ESI) m/z: 345 (6%, [M]+), 135 (100%, [Ad]+). Anal. (C20H31N3O2.) C 69.58%, H 9.10%, N 12.11%.

N-(Adamant-1-ylmethyl)-2-(5-methylisoxazol-3-yl)pyrrolidine-1-carboxamide (3j). The general method above was used with 5-methyl-3-(pyrrolidin-2-yl)isoxazole (2j) to afford a white solid (320 mg, 93% yield). Mp 176-177°С. IR spectrum, ν, cm-1: 1626 (С=O), 3341 (N–H). 1H NMR spectrum, δ, ppm (J, Hz): 6.09 (1H, s, H-4 Iz); 5.68 (1Н, br. s, NH); 4.94 (1H, d, J = 6.9, 2-CH pyrrolidine); 3.57-3.41 (1Н, m), 3.42-3.30 (2Н, m) and 3.01-2.89 (1Н, m, AdCH2NH, 5-СН2 pyrrolidine); 2.34 (3Н, s, CH3); 2.25-2.07 (1H, m, 3-CHA pyrrolidine); 1.89 (6Н, br. s, 3CH Ad, 3-CHВ pyrrolidine, 4-СН2 pyrrolidine); 1.67-1.49 (6Н, m, 3CH2 Ad); 1.33 (6H, s, 3CH2 Ad). 13C NMR spectrum, δ, ppm: 169.0 (С-5 Iz); 166.6 (С-3 Iz); 156.3 (СО); 100.4 (С-4 Iz); 52.3; 51.1; 45.8; 39.7 (2,8,9-CН2 Ad); 36.5 (4,6,10-CН2 Ad); 33.6 (C-1 Ad); 31.7; 27.7 (3,5,7-СH Ad); 23.5; 11.7 (CH3). MS (ESI) m/z: 343 (4%, [M]+), 135 (100%, [Ad]+). Anal. (C20H29N3O2) C 69.82%, H 8.71%, N 12.24%. N-(Adamant-1-ylmethyl)-2-(5-isopropylisoxazol-3-yl)pyrrolidine-1-carboxamide (3k). The general method above was used with 5-isopropyl-3-(pyrrolidin-2-yl)isoxazole (2k) to afford a white solid (193 mg, 52% yield). Mp 128-129°С. IR spectrum, ν, cm-1: 1649 (С=O), 3375 (N–H). 1H NMR spectrum, δ, ppm (J, Hz): 6.09 (1H, s, H-4 Iz); 5.72 (1Н, t, J = 5.6, NH); 4.95 (1H, d, J = 7.0, 2-CH pyrrolidine); 3.51-3.44 (1Н, m) and 3.40-3.25 (1Н, m, 3-СН2 pyrrolidine); 3.12-2.95 (1Н, m) and 2.66-2.49 (1Н, m, AdСН2NH); 2.96-2.81 (1Н, m, СНМе2); 2.18 (1Н, s, 3-CHA pyrrolidine); 1.90 (6Н, br. s, 3CH Ad, 3-CHВ pyrrolidine, 4-СН2 pyrrolidine); 1.70-1.51 (6Н, m, 3CH2 Ad); 1.32 (6H, s, 3CH2 Ad); 1.21 (6Н, d, J = 6.0, CH(CH3)2).

13C NMR spectrum, δ, ppm: 177.7 (С-5 Iz); 166.3 (С-3 Iz); 156.3 (СО); 98.0 (С-4 Iz); 52.4; 51.1; 45.9; 39.7 (2,8,9-CН2 Ad); 36.6 (4,6,10-CН2 Ad); 33.7 (C-1 Ad); 31.8; 27.7 (3,5,7-СH Ad); 26.4; 23.5; 20.6 (CH3); 20.5 (CH3). MS (ESI) m/z: 371 (5%, [M]+), 135 (100%, [Ad]+). Anal. (C22H33N3O2) C 71.08%, H 8.98%, N 11.25%. 1-(Adamant-1-ylmethyl)-3-[(3-isopropylisoxazol-5-yl)methyl]-3-methylurea (3l). The general method above was used with N-methyl-(3-isopropylisoxazol-5-yl)methylamine (2l) to afford a white solid (286 mg, 83% yield). Mp 146-148°С. IR spectrum, ν, cm-1: 1629 (С=O), 3377 (N–H). 1H NMR spectrum, δ, ppm (J, Hz): 6.25 (1H, t, J = 5.6, NH); 6.19 (1H, s, H-4 Iz); 4.53 (2H, s, NCH2Iz); 3.05-2.90 (1Н, m, СНМе2); 2.87 (3Н, s, NCH3); 2.76 (2H, d, J = 5.9, AdCH2NH); 1.89 (3Н, br. s, 3CH Ad); 1.70-1.51 (6Н, m, 3CH2 Ad); 1.37 (6H, s, 3CH2 Ad); 1.19 (6Н, d, J = 6.0, CH(CH3)2).

13C NMR spectrum, δ, ppm: 169.8 (С-5 Iz); 168.6 (С-3 Iz); 157.8 (СО); 99.9 (С-4 Iz); 51.5 (NCH2Iz); 43.9(NCH3); 39.9 (2,8,9-CН2 Ad); 36.6 (4,6,10-CН2 Ad); 34.6 (AdCH2NH); 33.9 (C-1 Ad); 27.7 (3,5,7-СH Ad); 25.8 (СНМе2); 21.4 (CH(CH3)2). MS (ESI) m/z: 345 (7%, [M]+), 135 (100%, [Ad]+). Anal. (C20H31N3O2) C 69.72%, H 9.08%, N 12.28%. N-(Adamant-1-ylmethyl)-2-(3-methylisoxazol-5-yl)pyrrolidine-1-carboxamide (3m). The general method above was used with 3-methyl-5-(pyrrolidin-2-yl)isoxazole (2m) to afford a white solid (320 mg, 93% yield). Mp 157-158°С. IR spectrum, ν, cm-1: 1627 (С=O), 3378 (N–H). 1H NMR spectrum, δ, ppm (J, Hz): 6.05 (1H, s, H-4 Iz); 5.96 (1Н, t, J = 5.2, NH); 5.07 (1H, d, J = 7.9, 2-CH pyrrolidine); 3.66-3.45 (1Н, m), 3.42-3.24 (2Н, m) and 3.03-2.88 (1Н, m, AdCH2NH, 5-СН2 pyrrolidine); 2.17 (3Н, s, CH3); 2.22-2.03 (1H, m, 3-CHА pyrrolidine); 1.89 (6Н, br. s, 3CH Ad, 3-CHВ pyrrolidine, 4-CH2 pyrrolidine); 1.71-1.49 (6Н, m, 3CH2 Ad); 1.34 (6H, s, 3CH2 Ad). 13C NMR spectrum, δ, ppm: 174.0 (С-5 Iz); 159.0 (С-3 Iz); 156.2 (СО); 101.6 (С-4 Iz); 52.7; 51.1; 45.6; 39.8 (2,8,9-CН2 Ad); 36.5 (4,6,10-CН2 Ad); 33.7 (C-1 Ad); 31.1; 27.7 (3,5,7-СH Ad); 23.4; 10.8 (СН3). MS (ESI) m/z: 343 (4%, [M]+), 135 (100%, [Ad]+). Anal. (C20H29N3O2) C 70.06%, H 8.76%, N 12.10%.\

Microsomal stability. The stability of the sEH inhibitors was determined using human liver microsomes as described.9 the inhibitors ([I]final = 1 M) to a suspension of human liver microsomes ([E]final= 1 mg/mL) in potassium phosphate buffer (0.1M pH7.4) containing 3mM MgCl2 and 1 mM EDTA. After 5 minutes incubation at 37 °C, the reaction was started by the addition of NADPH generating system (buffer was added in the control tubes). After 30 minutes at 37 °C, the reaction was stopped by the addition of one volume of methanol containing CUDA (200 nM) as surrogate. The amount of remaining inhibitors were determine by LC/MS/MS. The stability is reported as a percentage of compound remaining after 30 minutes in these conditions. Results are triplicate average.

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