Synthesis, hypolipidemic and antifungal activity of tetrahydroberberrubine sulfonates

Article abstract of DOI:10.1007/s11172-019-2519-y

The paper describes the synthesis of new tetrahydroberberrubine derivatives containing polyfl uorophenyl- or alkylsulfonate groups at the O(9) position as well as those containing or not containing a bromine atom at the C(12) position. In a model of acute Triton-induced hyperlipidemia, tetrahydroberberrubine 9-O-(heptafluoro-4’-toluene)sulfonate was shown to reduce the cholesterol level by 23.5%, which is comparable with the eff ect of Simvastatin. At a concentration of 32 μg mL^?1, tetrahydroberberrubine 9-O-pentafluorobenzenesulfonate inhibits the growth of the fungus Cryptococcus neoformans by 81.3±3.5%.

Full text of DOI:10.1007/s11172-019-2519-y

Russian Chemical Bulletin, International Edition, Vol. 68, No. 5, pp. 1052—1060, May, 2019
1052
Synthesis, hypolipidemic and antifungal activity of
tetrahydroberberrubine sulfonates*
I. V. Nechepurenko,a E. D. Shirokova,a,b M. V. Khvostov,a,b T. S. Frolova,b,c
O. I. Sinitsyna,b,c A. M. Maksimov,a R. A. Bredikhin,a N. I. Komarova,a D. S. Fadeev,a
O. A. Luzina,a T. G. Tolstikova,a and N. F. Salakhutdinova,b
aN. N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, Siberian Branch of the Russian Academy of Sciences,
9 prosp. Akad. Lavrentieva, 630090 Novosibirsk, Russian Federation.
Fax: +7 (383) 330 9752. Е-mail: niv@nioch.nsc.ru
bNovosibirsk State University,
2 ul. Pirogova, 630090 Novosibirsk, Russian Federation
cInstitute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences,
10 prosp. Akad. Lavrentieva, 630090 Novosibirsk, Russian Federation.
Fax: +7 (383) 333 1278
The paper describes the synthesis of new tetrahydroberberrubine derivatives containing
polyfluorophenyl- or alkylsulfonate groups at the O(9) position as well as those containing or
not containing a bromine atom at the C(12) position. In a model of acute Triton-induced hyper-
lipidemia, tetrahydroberberrubine 9-O-(heptafluoro-4´-toluene)sulfonate was shown to reduce
the cholesterol level by 23.5%, which is comparable with the effect of Simvastatin. At a concen-
tration of 32 μg mL–1, tetrahydroberberrubine 9-O-pentafluorobenzenesulfonate inhibits the
growth of the fungus Cryptococcus neoformans by 81.3 3.5%.
Key words: berberine, berberrubine, sulfonate, cholesterol, hyperlipidemia, antifungal
activity, Cryptococcus neoformans, cytotoxicity.
The isoquinoline alkaloid berberine (1) is one of the
most abundant members of the protoberberine alkaloid
family.1 Berberine has a broad spectrum of biological
activity, with antibacterial, antimalarial, and antitumor
activities studied in most detail.2—4 In recent years, ber-
berine was also extensively investigated as an agent ca-
pable of reducing the lipid level.5 Berberine has a different
mechanism of hypolipidemic effect compared to statins,
which are most commonly used agents for the treatment
of dyslipidemia. Statins are structurally similar to the
substrate of HMG-CoA reductase, with the result that
they block the biosynthetic pathway of farnesyl pyrophos-
phate, which is further converted not only into cholesterol
but also into sterol, ubiquinone, and dolichol. Besides,
statins have side effects, including increased concentrations
of liver enzymes in the blood, myopathy and myalgia,
rhabdomyolysis, and so on.6 Another drawback of statins
is that they induce an upregulation of the proprotein con-
vertase subtilisin/kexin type 9 (PCSK9), which suppre-
sses the expression of low-density lipoprotein receptors
(LDLRs), thereby reducing the removal cholesterol-
containing lipoproteins from the blood and offsetting
beneficial effects of statins. Unlike statins, berberine does
not inhibit cholesterol synthesis, but increases LDLR
expression and was shown to inhibit PCSK9 expression,
resulting in lowering of cholesterol levels in the blood and
an increase in the efficacy of statins.7
It is known that modifications of the berberine mol-
ecule can give rise to compounds with a more pronounced
hypolipidemic effect compared to the starting berberine.
The modification of the berberine moiety at the O(9)
position in order to prepare new biologically active com-
pounds is a very popular line of research. We consider such
compounds as derivatives of berberrubine (2), which is the
demethylated analog of berberine. Thus, we showed that
reduced berberine derivatives, such as 12-bromotetra-
hydroberberine (3) containing a bromine atom at C(12)
and 9-O-tosyltetrahydroberberrubine (4) containing the
sulfonate moiety at position 9, exhibit a pronounced hypo-
cholesterolemic effect in vivo. In the experiment using
Triton WR-1339-induced hyperlipidemic mice, com-
pound 3 decreased the level of total cholesterol in the
blood by 27%; compound 4, by 33%.8 In in vitro experi-
ments, it was demonstrated that reduced berberine de-
rivatives 5 and 6 containing the mono- and difluorinated
phenylsulfonate group, respectively, increase the level of
LDLR expression by a factor of 3.6—4.0.9 An interesting
* Dedicated to Corresponding Member of the Russian Academy
of Sciences A. V. Kutchin on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1052—1060, May, 2019.
1066-5285/19/6805-1052 © 2019 Springer Science+Business Media, Inc.

Synthesis of tetrahydroberberrubine sulfonates
Russ. Chem. Bull., Int. Ed., Vol. 68, No. 5, May, 2019
1053
R = Alk, CO—Alk
issue is the combined effect of the bromine atom and the
sulfonate group, as pharmacophore moieties, on biologi-
cal activity.
to the elimination of the methyl group at the O(9) atom
to form berberrubine (2). After the treatment with HBr,
the reaction product was isolated in 89% yield as a salt
— berberrubine hydrobromide (9) (Scheme 1). According
to the published data, berberrubine 2 reacted with a solu-
tion of bromine in aqueous alkali to form 12-bromoberber-
rubine (10) (the yield was not reported).15 We found that
the reaction under these conditions gave compound 10
only in trace amounts. The use of a dioxane—water mix-
ture as the solvent resulted in the bromination of com-
pound 9 giving bromo derivative 10 in 53% yield.
The modifications of berberine at the O(9) position
giving compounds with different biological activities were
described in the literature in detail. It was shown that
compounds 7 containing the trifluoromethyl-substituted
phenylsulfonate group have anti-inflammatory activity and
suppress the expression (with an inhibitory rate of 85—87%)
of nuclear factor-kappa B (NF-κB), which controls the
expression of immune response genes, apoptosis, and cell
cycle progression.10 Some 9-O-alkyl- and acyl-substituted
berberines 8 exhibit high activity against fungi (Crypto-
coccus neoformans ATCC 3655611,12) and bacteria (Staph-
ylococcus aureus,12 Micrococcus luteus13). These data
suggest that 9-O-substituted berberine derivatives should
be screened not only for hypolipidemic activity but also
for other activities.
In the present work, we synthesized a series of berber-
rubine (berberine) derivatives, namely, tetrahydroberber-
rubine 9-O-sulfonates containing polyfluorophenyl- and
alkylsulfonate groups. To test the hypothesis that the
pharmacophore moieties have a combined effect,8 we syn-
thesized analogs of tetrahydroberberrubine sulfonates con-
taining a bromine atom at the C(12) position. The synthe-
sized berberrubine derivatives were examined for hypolipid-
emic activity in vivo using a model of Triton-induced
hyperlipidemia. We also evaluated antibacterial and antifun-
gal activity of these compounds and their cytotoxic effect.
Synthesis of berberrubine derivatives. The heating of
berberine chloride (1) at 190 °C in vacuo (20 Torr)14 leads
Compound 9 was reduced with sodium borohydride in
methanol according to a procedure described previously.8
Tetrahydroberberrubine (11) was prepared in 78% yield.
The bromination of compound 11 with a solution of brom-
ine in dioxane afforded 12-bromotetrahydroberberrubine
hydrobromide (12) in 52% yield. Compound 12 was also
synthesized in 61% yield by the reduction of compound 10
with sodium borohydride in methanol.
The reaction of tetrahydro derivatives 11 and 12 with
polyfluoroaryl and alkyl sulfonyl chlorides as well as with
tosyl chloride in dichlorometane in the presence of triethyl-
amine produced tetrahydroberberrubine 9-O-sulfonates
13a—g (44—84% yields) and 12-bromotetrahydroberber-
rubine 9-O-sulfonates 14a—h (49—93% yields) (Scheme 2).
The structures of compounds 13 and 14 were established
1
based on the analysis of H, 13C, and 19F NMR spectra,
elemental analysis data, high-resolution mass spectra, and
IR and UV spectra. For compounds 13a and 14h, 2D cor-
relation spectra (H—H, C—H, COLOC, NOESY) were
recorded.

1054
Russ. Chem. Bull., Int. Ed., Vol. 68, No. 5, May, 2019
Nechepurenko et al.
Scheme 1
Reagents and conditions: (a) 190 °C, 20 Torr, 30 min; (b) HBr; (c) Br2/NaOH, dioxane—water; (d) NaBH4, MeOH; (e) Br2, dioxane.
Evaluation of hypolipidemic activity. The ability of
sulfonates 13a—g and 14a—h to reduce in vivo cholesterol
and triglyceride levels in the blood was evaluated using
a model of acute hyperlipidemia induced by the intra-
peritoneal administration of Tyloxapol (Triton WR1339).
Triton WR1339 is a nonionic detergent that induces hyper-
lipidemia by inhibiting peripheral lipoprotein lipase en-
zymes, which are responsible for removal of lipid particles
from the body, resulting in transient elevation of lipid
levels.16 The lipid level reaches a peak at 18—24 h after
the administration of Triton WR1339 and then starts
to decline.17
terolemic activity (cf. pairs of compounds 13c—14c and
48—14h). To evaluate this fact, further research on the
mechanism of action of sulfonates and their possible bind-
ing site is needed.
Scheme 2
Compounds 13a—g and 14a—h were administered to
mice once a day for four days at a dose of 100 mg kg–1
.
Previously, it was shown that other berberine derivatives
injected at this dose exhibit hypocholesterolemic effect.8
After the last administration of compounds 13 and 14, all
animals, except for the control group, were injected with
Tyloxapol. The animals were sacrificed 24 h after the injec-
tion, and the blood was collected for analysis. The drug
Simvastatin at a dose of 40 mg kg–1 was used as the refer-
ence. Table 1 summarizes the cholesterol and triglyceride
(TG) levels evaluated after the introduction of compounds
13a—g and 14a—h.
In the series of the compounds under study, only com-
pound 13c (R = p-CF3C6F4) displays hypocholesterolemic
effect. It causes a lowering of the cholesterol level by 23.5%.
The efficacy of 13c is comparable with that of Simvastatin
(reduces the cholesterol level by 26.9%). These compounds
had no effect on the triglyceride level.
i. NEt3, CH2Cl2.
13, 14
R
C6F5
13, 14
R
13, 14
g
h
R
a
b
c
d
e
f
Me
Et
Bun
As can be seen in Table 1, the introduction of a bromine
atom at the C(12) position leads to a loss of hypocholes-
p-HC6F4
p-CF3C6F4
p-MeC6H4
Prn

Synthesis of tetrahydroberberrubine sulfonates
Russ. Chem. Bull., Int. Ed., Vol. 68, No. 5, May, 2019
1055
Table 1. Hypolipidemic activity of tetrahydroberberrubine
sulfonates in a model of Triton-induced hyperlipidemia at
a dose of 100 mg kg–1
able antifungal agents are inefficient, toxic, and expen-
sive.20 Compound 13a showed 81.3 3.5% inhibition of
C. neoformans (100% for the reference agent Fluconazole).
The efficacy of compound 13a can be enhanced by trans-
forming it into hydrobromide. For compound 13a•HBr,
the inhibition of C. neoformans was 93.7 3.8% at a con-
centration of 32 μg mL–1. Other analogs of compound
13a, including those containing a bromine atom (14a,c,h),
did not exhibit significant activity against C. neoformans;
the minimal inhibitory concentration (MIC) of berberine
is 64 μg mL–1 in the inhibition of C. neoformans.21
Evaluation of cytotoxic activity. Compounds 13a—g
and 14a—e,g,h were tested for cytotoxic activity against
the tumor cell lines MCF7 (ATCC HTB-22) and HepG2
(ATCC HB-8065) and immortalized human fibroblasts
used as the normal cell line. Compounds 13b,e—g and
14b—e,g,h did not exhibit activity against all the cell lines
under study (IC50 > 100 μmol L–1). Table 2 summarizes
the concentrations of the compounds that cause 50% cell
growth inhibition (IC50) after 72 h incubation. Four com-
pounds (13a,c,d and 14a) displayed moderate cytotoxicity
against human fibroblasts.
In summary, we synthesized new tetrahydroberberine
derivatives modified at one or two positions: at position
12 by introducing bromine and/or at position 9 by alkyl-
and polyfluoroarylsulfonate moieties. Compound 13c
containing the perfluoro-para-toluenesulfonate substitu-
ent at position 9 and a bromine atom at position 12 dis-
played hypocholesterolemic effect in in vivo assays in mice
comparable with that of Simvastatin. In the absence of
a bromine substituent and in the presence of other sub-
stituents in the sulfonate group, the activity is lost. The
screening of antibacterial activity revealed that at a con-
centration of 32 μg mL–1, compound 13a containing the
perfluorophenylsulfonate and bromine substituents inhib-
its the growth of the fungus C. neoformans.
Compound
Cholesterol
mmol L–1
TG
Control
2.789 0.29
16.42 0.98
0.99 0.30
16.73 0.14
Triton WR1339
Simvastatin (40 mg kg–1
)
12.00 0.87* 16.76 0.29
13a
13b
13c
13d
13e
13f
13g
14a
14b
14c
14d
14e
14f
16.16 0.35
16.91 0.82
12.56 1.11*
16.71 1.21
15.92 1.07
15.35 2.09
15.89 0.76
16.03 0.77
15.62 1.23
16.34 1.73
16.43 0.75
15.57 2.09
18.83 1.28
17.87 1.29
15.01 1.12
17.59 0.34
16.95 0.34
16.42 2.93
16.59 0.09
15.11 0.18
15.70 2.09
15.57 0.27
16.64 0.20
18.40 0.91
15.16 0.34
16.85 0.28
16.54 2.07
15.92 0.19
15.84 0.25
16.87 0.16
14g
14h
* The criterion of statistically significant differences between
the results of evaluation compared to Triton WR1339 p ≤ 0.05.
Evaluation of antimicrobial activity. Antimicrobial activ-
ity of compounds 13a,d—e and 14a,c—e,h was kindly
evaluated by The Community for Antimicrobial Drug
Discovery (CO-ADD, Australia).18 The compounds were
tested for activity against Gram-negative (multi-drug re-
sistant Escherichia coli and Klebsiella pneumoniae strains,
Acinetobacter baumannii, and Pseudomonas aeruginosa)
and Gram-positive (methicillin-resistant Staphylococcus
aureus (MRSA) strain) bacteria and against the fungi
Candida albicans and Cryptococcus neoformans. The pre-
liminary antimicrobial screening was performed using
whole cell growth inhibition assays. Each compound was
tested at a concentration of 32 μg mL–1. The antibacterial
activity was compared with the effect of the drugs Van-
comycin and Amoxicillin; the antifungal activity, with the
effect of the drug Fluconazole.
Experimental
Berberine chloride hydrate purchased from TCI (percent
purity 81%) and a 48% aqueous HBr solution were used. Column
chromatography was carried out on neutral alumina LL40/250;
The tested compounds did not exhibit antibacterial
activity against the Gram-positive and Gram-negative
bacterial strains (the percentage of growth inhibition
compared with the reference agent was less than 25%). At
a concentration of 32 μg mL–1, compound 13a showed
high activity against the fungus Cryptococcus neoformans.
This fungus is an encapsulated organism, which usually
grows in central nervous system tissues, although it can
grow in other tissues of the body. This fungus causes the
damage of the central nervous system and, in some cases,
the lungs, mucosal and skin lesions.19 Currently, there are
no effective vaccines against cryptococcosis, and the avail-
Table 2. Cytotoxic activity of tetrahydroberberrubine sulfonates
Compound
IC50 SEM/μmol L–1
IFs*
MCF7
HepG2
Doxorubicin
4.2 0.7
17.46 0.88
<10
15.06 2.43
20.92 2.3
3.17 0.41
43.57 3.43
>100
11.23 2.38
>100
13a
13c
13d
14a
>100
>100
>100
48.56 5.7
78.93 2.95
* IFs are immortalized fibroblasts.

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Russ. Chem. Bull., Int. Ed., Vol. 68, No. 5, May, 2019
Nechepurenko et al.
HPLC, on a Milichrom A-02 micro-column liquid chromato-
graph (EcoNova, Novosibirsk) equipped with standard chrom-
atography columns packed with the reversed-phase sorbent
ProntoSIL-120-5-C18 AQ (particle size 5 μm, 75×2 mm column) at
off and dried in a desiccator. Compound 10 was obtained in
a yield of 347 mg (53%). The melting point was not determined
(decomp.). Found (%): C, 46.73; H, 3.28; N, 2.43; Br, 32.91.
C19H15NO4Br2. Calculated (%): C, 47.43; H, 3.14; N, 2.91; Br,
35 °C; the pressure was 30—36 atm; the flow rate was 150 μL min–1
.
33.21. UV (EtOH), λmax/nm: 239; 279; 356. IR (KBr), ν/cm–1
:
The injection volume was 2 μL. The linear gradient elution was
peformed using the solvent system, from 100% A to 100% B for
25 min (solvent A, 0.1% aqueous trifluortoacetic acid solution;
solvent B, methanol), with multi-wavelength detection at six
wavelengths (220, 240, 260, 280, 320, 360 nm).
1315; 1497; 1591. MS (LC-MS): found: m/z 400.016 [M – Br]+;
C19H15NO4Br+; calculated: 400.018. 1H NMR (400 MHz,
DMSO-d6), δ: 3.13—3.23 (m, 2 H, H(5)); 4.05 (s, 3 H, OCH3);
4.86—4.97 (m, 2 H, H(6)); 6.17 (s, 2 H, OCH2O); 7.06 (s, 1 H,
H(4)); 7.82 (s, 1 H, H(1)); 8.31 (s, 1 H, H(11)*); 8.32 (s, 1 H,
H(13)*); 9.97 (s, 1 H, H(8)); 11.67 (br.s, 1 H, OH). 13C NMR
(100 MHz, DMSO-d6), δ: 26.37 (C(5)), 54.97 (C(6)), 57.50
(OCH3), 102.17 (OCH2O), 105.80 (C(1)), 108.44 (C(4)), 108.64
(C(12)), 117.94 (C(11)), 118.06 (C(13b)), 120.24 (C(8a)), 128.46
(C(13)), 130.24 (C(12a)*), 131.12 (C(4a)*),138.06 (C(13a)),
144.44, 145.52 (C(2), C(3)), 147.80 (C(9)), 150.01 (C(10)).
Tetrahydroberberrubine (11). Sodium borohydride (1.35 g,
4 equiv.) was added portionwise to a magnetically stirred suspen-
sion of berberrubine hydrobromide dihydrate 9 (3.88 g, 8.86 mmol)
in methanol (30 mL) at 0 °C. The reaction mixture was stirred
at room temperature for 2.5 h. The solvent was distilled off
in vacuo, and the residue was dissolved in CH2Cl2 and passed
through an alumina layer. The fractions of the eluate containing
the product were combined, and the solvent was distilled off
in vacuo. The residue was recrystallized from acetonitrile.
Compound 11 was obtained in a yield of 2.14 g (74%). The spectro-
scopic data are consistent with those published in the literature.22
12-Bromotetrahydroberberrubine hydrobromide (12). A. A solu-
tion of bromine (3.53 g, 22.08 mmol) in dioxane (15 mL) was
added dropwise to a mechanically stirred solution of tetra-
hydroberberrubine 11 (2.39 g, 7.36 mmol) in dioxane (50 mL)
at room temperature, during which a brown-red precipitate
formed. Then the reaction mixture was stirred for 3 h at room
temperature. The precipitate was filtered off and successively
washed with a saturated Na2SO3 solution (4×20 mL) and aceto-
nitrile (3×10 mL). The residue was refluxed with methanol
(80 mL) for 30 min and then cooled. The precipitate was filtered
off and dried in a desiccator. Compound 12 was obtained in
a yield of 1.87 g (52%).
The spectroscopic and analytical measurements were carried
out at the Multi-access Chemical Service Center of the Siberian
Branch of the Russian Academy of Sciences. The melting points
were measured on a Mettler Toledo thermosystem. The UV
spectra were recorded on a HP 8453 UV-Vis spectrophotometer
in EtOH (c = 10–4 mol L–1). The IR spectra were measured on
a Vector 22 FTIR spectrometer in KBr pellets. High-resolution
mass spectra were obtained on a DFS Thermo Scientific mass
spectrometer; LC-MS, on a HPLC-MS system comprising an
Agilent 1200 liquid chromatograph and a Bruker micrOTOF-Q
hybrid quadrupole time-of-flight mass spectrometer. The mass
detection parameters were as follows: the atmospheric pressure
ionization electrospray (API-ES) mode, the positive ion scan in
the range m/z = 100—3000. The nebulizer gas (nitrogen) flow
rate was 4 L min–1, the temperature was 220 °C, the pressure at
the spraying nozzle was 1.0 atm. A solution of the compound
(2 μL) at a concentration of 0.1 mg mL–1 in methanol was intro-
duced into an electrospray ionization chamber of the mass
spectrometer by injecting it into the solvent flow (MeOH, 0.1 mL
min–1) using an autosampler device. The 1H and 13C NMR
spectra were recorded on a Bruker AM-400 spectrometer (400.13
and 100.61 MHz) for 5—10% solutions of the compounds in
CDCl3 or DMSO-d6 using the signal of the solvent CDCl3 as the
standard (δ 7.24 for 1H and δ 76.90 for 13C). The 19F NMR spec-
tra were measured on a Bruker AV-300 spectrometer (282.36 MHz)
using C6F6 (δ –162.9 with respect to the signal of CFCl31) as the
external standard. The assignments of the signals in the H and
13C NMR spectra marked with an asterisk and a double asterisk
can be interchanged.
Berberrubine hydrobromide (9). Compound 1 (5 g, 0.011 mol)
was heated in a 2 L flask on a sand bath at 180—200 °C using
a water-jet vacuum (20—30 Torr) five times for 15 min. Between
the heatings, the reaction mixture was stirred to homogeneity.
The dark-maroon residue was dissolved in hot ethanol (200 mL)
and then filtered. After cooling, concentrated HBr (3 mL) was
added. The mixture was cooled and a precipitate of berberrubine
hydrobromide dihydrate 9 was filtered off. The yield was 4.18 g
(89%). The 1H NMR spectroscopic data are consistent with those
published in the literature.22
12-Bromoberberrubine hydrobromide (10). A solution of
bromine (480 mg, 3.00 mmol) in a 6% aqueous NaOH solution
(9 mL) was added dropwise to a magnetically stirred solution of
berberrubine hydrobromide dihydrate 9 (595 mg, 1.36 mmol) in
a mixture of dioxane (5 mL) and water (20 mL), during which
a precipitate formed. Then the reaction mixture was stirred for
1 h at room temperature. The dark-cherry precipitate was filtered
off, washed with a small amount of water, and dried in a desic-
cator. Then the precipitate was suspended in methanol (10 mL)
and acidified with hydrobromic acid to acidic pH. The remaining
precipitate was dissolved, after which a paler precipitate formed.
The mixture was cooled, and the orange precipitate was filtered
B. Sodium borohydride (116 mg, 3.04 mmol) was added
portionwise to a magnetically stirred suspension of aromatic
hydrobromide 10 (244 mg, 0.51 mmol) in MeOH (5 mL) at 0 °C.
The reaction mixture was stirred for 30 min at 0 °C and then for
1.5 h at room temperature. The solvent was removed in vacuo,
and the residue was separated by chromatography on silica gel
(CH2Cl2—MeOH, 100 : 1). The recrystallization from aceto-
nitrile gave compound 12 as a free base in a yield of 90 mg (44%).
The mother liquor was acidified with HBr, and compound 12 as
hydrobromide was additionally filtered off in a yield of 42 mg
(17%). M.p. 289.9 °C (decomp.). Found (%): C, 42.74; H, 3.96;
N, 2.61; Br, 30.11. C19H19NO4Br2•3 H2O. Calculated (%):
C, 42.32; H, 4.67; N, 2.60; Br, 29.64. UV (EtOH), λmax/nm:
205; 290. IR (KBr), ν/cm–1: 1296; 1498. MS (LC-MS): found:
m/z 404.051 [M – Br]+; C19H19NO4Br+; calculated: 404.049.
1H NMR (400 MHz, DMSO-d6), δ: 2.69—2.76 (m, 1 H, H(13));
2.91—2.95 (m, 1 H, H(5)); 2.09—3.23 (m, 2 H, H(5), H(6));
3.66 (m, 1 H, H(13)); 3.85 (s, 3 H, OCH3); 3.95 (m, 1 H, H(6));
4.32—4.35 (m, 1 H, H(8)); 4.57—4.65 (m, 2 H, H(8), H(13a));
6.04 (d, 2 H, OCH2O, J = 11.5 Hz); 6.84 (s, 1 H, H(4)); 7.16
(s, 1 H, H(1)); 7.29 (s, 1 H, H(11)); 9.71 (s, 1 H, OH); 10.44
(s, 1 H, NH+). 13C NMR (125 MHz, DMSO-d6), δ: 25.65 (C(5)),

Synthesis of tetrahydroberberrubine sulfonates
Russ. Chem. Bull., Int. Ed., Vol. 68, No. 5, May, 2019
1057
34.29 (C(13)), 49.88 (C(6)), 51.06 (C(8)), 56.66 (OCH3), 59.07
(C(13a)), 101.59 (OCH2O), 105.82 (C(1)), 108.50 (C(4)), 111.95
(C(12)), 115.34 (C(11)), 118.30 (C(8a)*), 123.68 (C(12a)*), 124.98
(C(13b)*), 125.50 (C(4a)*), 142.30 (C(9)), 146.79, 147.02, 147.18
(C(2), C(3), C(10)).
Synthesis of sulfonates 13 and 14 (general procedure). Tri-
ethylamine (2.5 mmol, 0.35 mL; 3.5 mmol in the case of hydro-
bromide 12) and sulfonyl chloride (1.5 mmol) were added
dropwise to a solution of compound 11 or 12 (1 mmol) in CH2Cl2
(20 mL) at room temperature. The reaction mixture was stirred
at room temperature for 5—8 h, the solvent was removed in vacuo,
and the residue was separated by chromatography on silica gel
(CHCl3—MeOH, 100 : 0, 100 : 1, 100 : 2). After the recrystal-
lization from MeCN, sulfonates 13 and 14 were obtained as
crystalline compounds.
ed (%): C, 51.58; H, 3.00; N, 2.31; S, 5.30; F, 21.96. UV (EtOH),
λmax/nm: 223; 228; 242; 289. IR (KBr), ν/cm–1: 1159; 1327;
1400; 1410; 1502. MS (HRMS): found: m/z 605.0738 [M]+;
C26H18NO6SF7; calculated: 605.0741. 1H NMR (300 MHz,
CDCl3), δ: 2.60—2.72 (m, 2 H, H(5), H(6)); 2.77—2.93 (m, 1 H,
H(13)); 3.02—3.29 (m, 3 H, H(5), H(6), H(13)); 3.47 (s, 3 H,
OCH3); 3.57—3.65 (m, 1 H, H(13a)); 3.71 (d, 1 H, H(8), J = 16 Hz);
4.28 (d, 1 H, H(8), J = 16 Hz); 5.90 (s, 2 H, OCH2O); 6.58
(s, 1 H, H(4)); 6.68 (s, 1 H, H(1)); 6.76 (d, 1 H, H(11), J = 8.4 Hz);
7.07 (d, 1 H, H(12), J = 8.4 Hz). 19F NMR (282 MHz, CDCl3),
δ: 24.2 (2 F, F(3´), F(5´)); 29.6 (m, 2 F, F(2´), F(6´)); 105.1
(t, 3 F, CF3, J = 22.0 Hz). 13C NMR (100 MHz, CDCl3), δ: 29.44
(C(5)), 36.02 (C(13)), 51.20 (C(6)), 53.70 (C(8)), 55.68 (OCH3),
59.36 (C(13a)), 101.00 (OCH2O), 105.52 (C(1)), 108.64 (C(4)),
113.15 (C(11)), 114.17 (qt, C(4´), 2J = 35 Hz, 2J = 12.5 Hz),
1
Tetrahydroberberrubine 9-O-pentafluorobenzenesulfonate
(13a). Yield 44%. M.p. 213.8 °C (decomp.). Found (%): C, 49.32;
H, 3.20; N, 2.44; S, 5.29; F, 15.73. C25H18NO6SF5+3H2O.
Calculated (%): C, 49.26; H, 3.97; N, 2.30; S, 5.26; F, 15.58.
UV (EtOH), λmax/nm: 202; 286. IR (KBr), ν/cm–1: 1290; 1400;
1504. MS (HRMS): found: m/z 555.0778 [M]+; C25H18NO6SF5;
calculated: 555.0770. 1H NMR (600 MHz, DMSO-d6), δ:
2.80—2.95 (m, 1 H, H(5)); 3.03—3.19 (m, 1 H, H(13)); 3.30
(m, 1 H, H(5)); 3.45 (m, 1 H, H(6)); 3.56 (s, 3 H, OCH3); 3.81—3.90
(m, 2 H, H(13), H(6)); 4.45—4.86 (m, 3 H, H(8), H(13a)); 6.03
(d, 2 H, OCH2O, J = 3.0 Hz); 6.83 (s, 1 H, H(4)); 7.09 (s, 1 H,
H(1)); 7.20 (d, 1 H, H(11), J = 8.7 Hz); 7.31 (d, 1 H, H(12),
J = 8.4 Hz). 19F NMR (282 MHz, DMSO-d6), δ: 5.8 (m, 2 F,
F(3´), F(5´)); 22.6 (t, 1 F, F(4´), J = 22.5 Hz); 28.5 (m, 2 F,
F(2´), F(6´)). 13C NMR (150 MHz, DMSO-d6), δ: 25.41 (C(5)),
31.93 (C(13)), 49.76 (C(6)), 50.26 (C(8)), 56.04 (OCH3), 58.66
(C(13a)), 101.28 (OCH2O), 105.54 (C(1)), 108.26 (C(4)), 112.94
(C(1´)), 113.15 (C(11)), 124.06 (C(8a)), 124.96 (C(13b)), 125.48
(C(4a)), 125.86 (C(12a), 129.14 (C(12)), 134.22 (C(9)), 137.66
(d, (C(2´), C(6´), 1J = 256 Hz), 144.40 (d, (C(3´), C(5´),
1J = 260 Hz), 144.94 (d, (C(4´), 1J = 258 Hz), 146.68, 146.87
(C(2), C(3)), 149.38 (C(10)).
Tetrahydroberberrubine 9-O-(2´,3´,5´,6´-tetrafluorobenzene)-
sulfonate (13b). Yield 84%. M.p. 113 °C (decomp.). Found (%):
C, 54.85; H, 2.41; N, 3.77; S, 6.35; F, 14.05. C25H19NO6SF4+H2O.
Calculated (%): C, 54.05; H, 2.52; N, 3.81; S, 5.77; F, 13.68. UV
(EtOH), λmax/nm: 205; 286. IR (KBr), ν/cm–1: 1253; 1393; 1504.
MS (HRMS): found: m/z 536.0782 [M – H]+; C25H18NO6SF4;
calculated: 536.0785. 1H NMR (300 MHz, CDCl3), δ: 2.60—2.72
(m, 2 H, H(5), H(6)); 2.77—2.92 (m, 1 H, H(13)); 3.04—3.28
(m, 3 H, H(5), H(6), H(13)); 3.46 (s, 3 H, OCH3); 3.58—3.66
(m, 1 H, H(13a)); 3.71 (d, 1 H, H(8), J = 16 Hz); 4.30 (d, 1 H,
H(8), J = 16 Hz); 5.90 (s, 2 H, OCH2O); 6.58 (s, 1 H, H(4));
6.68 (s, 1 H, H(1)); 6.74 (d, 1 H, H(11), J = 8.4 Hz); 7.04 (d, 1 H,
H(12), J = 8.4 Hz); 7.39 (tt, 1 H, H(4´), J = 9.0 Hz, J = 7.1 Hz).
19F NMR (282 MHz, CDCl3), δ: 25.7 (m, 2 F); 27.1 (m, 2 F).
13C NMR (100 MHz, CDCl3), δ: 29.10 (C(5)), 35.68 (C(13)),
50.91 (C(6)), 53.47 (C(8)), 55.40 (OCH3), 59.11 (C(13a)), 100.72
(OCH2O), 105.26 (C(1)), 108.35 (C(4)), 110.65 (C(11)), 110.78
(C(4´)), 119.45 (C(1´)), 127.44 (C(8a*)), 128.24 (C(13b*)),
128.24 (C(12)), 129.87 (C(4a)*), C(12a)*), 135.37 (C(9)), 143.61
(d, C(2´), C(6´), 1J = 262 Hz), 146.15 (d, C(3´), C(5´), 1J = 251 Hz),
146.01, 146.12 (C(2), C(3)), 148.80 (C(10)).
120.24 (q, CF3, J = 275 Hz), 122.66 (C(1´)), 127.73 (C(8a)*),
128.75 (C(13b*), 128.75 (C(12)), 130.17 (C(4a)*, C(12a)*), 135.58
(C(9)), 144.30, 144.52 (both d, C(2´), C(6´), C(3)´, C(5´),
1J = 264 Hz), 146.30, 146.41 (C(2), C(3)), 148.75 (C(10)).
Tetrahydroberberrubine 9-O-methylsulfonate (13d). Yield
76%. M.p. 191.3 °C (decomp.). Found (%): C, 59.50; H, 5.06;
N, 3.78; S, 7.85. C20H21NO6S. Calculated (%): C, 59.54; H, 5.25;
N, 3.47; S, 7.95. UV (EtOH), λmax/nm: 201; 286. IR (KBr),
ν/cm–1: 1173; 1229; 1286; 1365; 1491. MS (HRMS): found: m/z
402.0998 [M – H]+; C20H20NO6S; calculated: 402.1006. 1H NMR
(300 MHz, CDCl3), δ: 2.56—2.68 (m, 2 H, H(5), H(6)); 2.80
(m, 1 H, H(13)); 2.99—3.27 (m, 3 H, H(5), H(6), H(13)); 3.32
(s, 3 H, CH3SO2O); 3.52—3.60 (m, 1 H, H(13a)); 3.65 (d, 1 H,
H(8), J = 16 Hz); 3.85 (s, 3 H, OCH3); 4.25 (d, 1 H, H(8),
J = 16 Hz); 5.89 (s, 2 H, OCH2O); 6.57 (s, 1 H, H(4)); 6.68
(s, 1 H, H(1)); 6.82 (d, 1 H, H(11), J = 8.4 Hz); 7.03 (d, 1 H, H(12),
J = 8.4 Hz). 13C NMR (125 MHz, CDCl3), δ: 29.32 (C(5)), 35.96
(C(13)), 39.54 (CH3SO2O), 50.93 (C(6)), 53.79 (C(8)), 55.79
(OCH3), 59.10 (C(13a)), 100.59 (OCH2O), 105.25 (C(1)), 108.25
(C(4)), 110.60 (C(11)), 127.55 (C(12)), 127.60 (C(8a)*), 128.25
(C(13b*)), 130.32, 130.57 (C(4a)*, C(12a)*), 135.30 (C(9)),
145.77, 145.95 (C(2), C(3)), 149.20 (C(10)).
Tetrahydroberberrubine 9-O-ethylsulfonate (13e). Yield 58%.
M.p. 186.5—187.0 °C. Found (%): C, 60.37; H, 5.34; N, 3.57;
S, 7.68. C21H23NO6S. Calculated (%): C, 60.42; H, 5.55; N, 3.36;
S, 7.68. UV (EtOH), λmax/nm: 201; 286. IR (KBr), ν/cm–1: 1286;
1358; 1500. MS (HRMS): found: m/z 417.1239 [M]+; C21H23NO6S;
calculated: 417.1241. 1H NMR (400 MHz, CDCl3), δ: 1.57 (t, 3 H,
CH3CH2, J = 8 Hz); 2.58—2.67 (m, 2 H, H(5), H(6)); 2.75—2.85
(m, 1 H, H(13)); 3.00—3.25 (m, 3 H, H(5), H(6), H(13));
3.39—3.54 (m, 2 H, CH2SO2O); 3.54—3.56 (m, 1 H, H(13a));
3.68 (d, 1 H, H(8), J = 16 Hz); 3.83 (s, 3 H, OCH3); 4.26 (d, 1 H,
H(8), J = 16 Hz); 5.88—3.91 (m, 2 H, OCH2O); 6.57 (s, 1 H,
H(4)); 6.68 (s, 1 H, H(1)); 6.81 (d, 1 H, H(11), J = 8.4 Hz); 7.02
(d, 1 H, H(12), J = 8.4 Hz). 13C NMR (100 MHz, CDCl3), δ:
8.42 (CH3CH2), 29.52 (C(5)), 36.16 (C(13)), 47.38 (CH2SO2O),
51.13 (C(6)), 54.06 (C(8)), 55.99 (OCH3), 59.31 (C(13a)), 100.80
(OCH2O), 105.47 (C(1)), 108.46 (C(4)), 110.78 (C(11)), 127.64
(C(12)), 127.80 (C(8a)*), 128.38 (C(13b*), 130.56, 130.91 (C(4a)*,
C(12a)*), 135.44 (C(9)), 145.98, 146.16 (C(2), C(3)), 149.43 (C(10)).
Tetrahydroberberrubine 9-O-propylsulfonate (13f). Yield 74%.
M.p. 179.9 °C (decomp.). Found (%): C, 61.08; H, 5.63; N, 3.31;
S, 7.37. C22H25NO6S. Calculated (%): C, 61.24; H, 5.84; N, 3.25;
S, 7.43. UV (EtOH), λmax/nm: 201; 286. IR (KBr), ν/cm–1: 1284;
1365; 1487. MS (HRMS): found: m/z 431.1396 [M]+; C22H25NO6S;
calculated: 431.1397. 1H NMR (400 MHz, CDCl3), δ: 1.12 (t, 3 H,
Tetrahydroberberrubine 9-O-(heptafluoro-4´-toluene)sulfonate
(13c). Yield 64%. M.p. 178.9 °C (decomp.). Found (%): C, 51.92;
H, 3.07; N, 2.59; S, 5.42; F, 21.87. C26H18NO6SF7. Calculat-

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Nechepurenko et al.
CH3CH2, J = 8 Hz); 2.06 (m, 2 H, CH3CH2); 2.58—2.67 (m, 2 H,
H(5), H(6)); 2.80 (m, 1 H, H(13)); 3.01—3.26 (m, 3 H, H(5),
H(6), H(13)); 3.42 (m, 2 H, CH2SO2O); 3.56 (m, 1 H, H(13a));
3.67 (d, 1 H, H(8), J = 16 Hz); 3.83 (s, 3 H, OCH3); 4.26 (d, 1 H,
H(8), J = 16 Hz); 5.89 (m, 2 H, OCH2O); 6.57 (s, 1 H, H(4));
6.68 (s, 1 H, H(1)); 6.81 (d, 1 H, H(11), J = 8.4 Hz); 7.02 (d, 1 H,
H(12), J = 8.4 Hz). 13C NMR (125 MHz, CDCl3), δ: 14.42
(CH3CH2), 18.90 (CH3CH2), 30.90 (C(5)), 37.53 (C(13)), 52.50
(C(6)), 55.46 (C(8*)), 55.80 (CH2SO2O*), 57.41 (OCH3), 60.70
(C(13a)), 102.17 (OCH2O), 106.85 (C(1)), 109.84 (C(4)), 112.24
(C(11)), 128.98 (C(12)), 129.19 (C(8a)**), 129.80 (C(13b**),
131.97, 132.30 (C(4a)**, C(12a)**), 136.90 (C(9)), 147.39, 147.56
(C(2), C(3)), 150.86 (C(10)).
Tetrahydroberberrubine 9-O-butylsulfonate (13g). Yield 83%.
M.p. 160.8 °C (decomp.). Found (%): C, 62.15; H, 5.95; N, 3.14;
S, 7.12. C23H27NO6S. Calculated (%): C, 62.00; H, 6.11; N, 3.14;
S, 7.20. UV (EtOH), λmax/nm: 201; 286. IR (KBr), ν/cm–1: 1225;
1290; 1356; 1483. MS (HRMS): found: m/z 445.1550 [M]+;
C23H27NO6S; calculated: 445.1554. 1H NMR (400 MHz, CDCl3),
δ: 0.99 (t, 3 H, CH3CH2, J = 8 Hz); 1.47—1.56 (m, 3 H,
CH3CH2); 1.96—2.06 (m, 2 H, CH3CH2CH2); 2.58—2.68
(m, 2 H, H(5), H(6)); 2.75—2.85 (m, 1 H, H(13)); 3.00—3.26
(m, 3 H, H(5), H(6), H(13)); 3.37—3.51 (m, 2 H, CH2SO2O);
3.53—3.61 (m, 1 H, H(13a)); 3.67 (d, 1 H, H(8), J = 16 Hz);
3.83 (s, 3 H, OCH3); 4.26 (d, 1 H, H(8), J = 16 Hz); 5.89 (m, 2 H,
OCH2O); 6.57 (s, 1 H, H(4)); 6.68 (s, H(1) 1 H); 6.81 (d, 1 H,
H(11), J = 8.4 Hz), 7.02 (d, 1 H, H(12), J = 8.4 Hz). 13C NMR
(100 MHz, CDCl3), δ: 13.41 (CH3CH2), 21.47 (CH3CH2), 25.47
(CH3CH2CH2), 29.35 (C(5)), 35.99 (C(13)), 50.97 (C(6)), 52.37
(CH2SO2O*), 53.91 (C(8*)), 55.83 (OCH3), 59.15 (C(13a)),
100.65 (OCH2O), 105.31 (C(1)), 108.31 (C(4)), 110.64 (C(11)),
127.45 (C(12)), 127.63 (C(8a)**), 128.20 (C(13b**), 130.38, 130.72
(C(4a)**, C(12a)**), 135.31 (C(9)), 145.83, 146.00 (C(2), C(3)),
149.28 (C(10)).
λmax/nm: 206; 288. IR (KBr), ν/cm–1: 1172; 1261; 1402; 1504.
MS (HRMS): found: m/z 614.9958 [M]+; C25H18NO6SF4Br;
calculated: 614.9969. 1H NMR (300 MHz, DMSO-d6), δ:
2.78—3.00 (m, 2 H, H(5), H(13)); 3.16—3.28 (m, 1 H, H(5));
3.45 (m, 1 H, H(6)); 3.53 (s, 3 H, OCH3); 3.72—4.06 (m, 2 H,
H(6), H(13)); 4.56—4.90 (m, 3 H, 2 H(8), H(13a)); 6.03 (d, 2 H,
OCH2O, J = 8.0 Hz); 6.84 (s, 1 H, H(4)); 7.15 (s, 1 H, H(1));
7.57 (s, 1 H, H(11)); 8.56 (tt, 1 H, H(4´), J = 10.3 Hz, J = 7.7 Hz);
11.47 (br.s, 1 H, NH+). 19F NMR (282 MHz, DMSO-d6), δ: 26.3
(m, 2 F); 26.4 (m, 2 F). 13C NMR (100 MHz, DMSO-d6), δ: 25.41
(C(5)), 34.11 (C(13)), 49.42 (C(6)), 50.04 (C(8)), 56.57 (OCH3),
58.50 (C(13a)), 101.32 (OCH2O), 105.53 (C(1)), 108.30 (C(4)),
113.96 (C(4´)), 116.98 (C(1´)), 117.11 (C(11)), 123.49 (C(12)),
124.63 (C(8a)*), 125.15, 125.35 (C(13b)*, C(4a)*), 126.29
(C(12a), 133.78 (C(9)), 143.60 (d, (C(2´), C(6´), 1J = 254 Hz);
145.74 (d, (C(3)´, C(5´), 1J = 253 Hz); 146,74, 146.98 (C(2),
C(3)), 149.91 (C(10)).
12-Bromotetrahydroberberrubine 9-O-(heptafluoro-4´-tolu-
ene)sulfonate (14c). Yield 49%. M.p. was not determined (de-
comp.). Found (%): C, 45.38; H, 2.36; N, 2.24; S, 4.86; F, 19.31;
Br, 12.72. C26H17NO6SF7Br. Calculated (%): C, 45.63; H, 2.50;
N, 2.02; S, 4.69; F, 19.43; Br,11.68. UV (EtOH), λmax/nm: 205;
289. IR (KBr), ν/cm–1: 1161; 1331; 1504. MS (HRMS): found:
m/z 682.9847 [M]+; C26H17NO6SF7Br; calculated: 682.9843.
1H NMR (400 MHz, CDCl3), δ: 2.57—2.72 (m, 3 H, H(5), H(6),
H(13)); 3.00—3.31 (m, 3 H, H(5), H(6), H(13)); 3.50 (s, 3 H,
OCH3); 3.55—3.63 (m, 1 H, H(13a)); 3.68 (d, 1 H, H(8),
J = 16 Hz); 4.25 (d, 1 H, H(8), J = 16 Hz); 5.92 (s, 2 H, OCH2O);
6.59 (s, 1 H, H(4)); 6.75 (s, 1 H, H(1)); 7.03 (s, 1 H, H(11)).
19F NMR (282 MHz, CDCl3), δ: 24.5 (m, 2 F, F(3´), F(5´));
29.7 (m, 2 F, F(2´), F(6´)); 105.1 (t, 3 F, CF3, J = 22.0 Hz).
13C NMR (100 MHz, CDCl3), δ: 29.19 (C(5)), 37.17 (C(13)),
50.55 (C(6)), 53.60 (C(8)), 55.72 (OCH3), 58.99 (C(13a)), 100.77
(OCH2O), 105.38 (C(1)), 108.36 (C(4)), 114.12 (qt, C(4´),
2J = 35 Hz, 2J = 12.5 Hz), 114.71 (C(11)), 119.92 (q, CF3,
1J = 275 Hz), 122.12 (C(1´)), 123.82 (C(12)), 127.44 (C(8a)*),
128.29 (C(13b*), 129.63 (C(4a)**), 131.98 (C(12a)**), 134.55
(C(9)), 144.05, 144.20 (both d,(C(2´), C(6´), C(3´), C(5´),
1J = 267 Hz), 146.09, 146.15 (C(2), C(3)), 148.79 (C(10)).
12-Bromotetrahydroberberrubine 9-O-methylsulfonate (14d).
Yield 93%. M.p. 234.2 °C (decomp.). Found (%): C, 50.50;
H, 4.26; N, 2.84; S, 6.51; Br, 16.12. C20H20NO6SBr. Calculated (%):
C, 49.80; H, 4.18; N, 2.90; S, 6.65; Br, 16.57. UV (EtOH),
λmax/nm: 205; 288. IR (KBr), ν/cm–1: 1165; 1222; 1361; 1483.
MS (HRMS): found: m/z 481.0186 [M]+; C20H20NO6SBr; cal-
culated: 481.0189. 1H NMR (400 MHz, DMSO-d6), δ: 2.30—2.38
(m, 1 H, H(13)); 2.44—2.48 (m, 1 H, H(5)*); 2.58—2.66 (m, 1 H,
H(6)*); 2.83—2.92 (m, 1 H, H(5)); 3.03—3.11 (m, 1 H, H(13));
3.26—3.32 (m, 1 H, H(6)); 3.46—3.49 (m, 1 H, H(13a)); 3.50
(s, 3 H, CH3SO2O); 3.52 (d, 1 H, H(8), J = 16 Hz); 3.87 (s, 3 H,
OCH3); 4.06 (d, 1 H, H(8), J = 16 Hz); 5.96 (d, 2 H, OCH2O,
J = 9.6 Hz); 6.68 (s, 1 H, H(4)); 6.95 (s, 1 H, H(1)); 7.38 (s, 1 H,
H(11)). 13C NMR (100 MHz, DMSO-d6), δ: 28.92 (C(5)), 36.95
(C(13)), 39.82 (CH3SO2O), 49.86 (C(6)), 53.52 (C(8)), 56.51
(OCH3), 58.54 (C(13a)), 100.67 (OCH2O), 105.78 (C(1)), 108.20
(C(4)), 115.12 (C(11)), 122.23 (C(12)), 127.13 (C(8a)**), 127.40
(C(13b)**), 130.31 (C(4a)**), 132.17 (C(12a), 134.38 (C(9)),
145.66, 145.80 (C(2), C(3)), 150.04 (C(10)).
12-Bromotetrahydroberberrubine 9-O-pentafluorobenzene-
sulfonate (14a). Yield 49%. M.p. was not determined (decomp.).
Found (%): C, 47.63; H, 3.23; N, 2.99; S, 5.30; F, 14.30; Br, 12.63.
C25H17NO6SF5Br. Calculated (%): C, 47.33; H, 2.70; N, 2.22;
S, 5.05; F, 14.97; Br, 12.60. UV (EtOH), λmax/nm: 204; 289. IR
(KBr), ν/cm–1: 1103; 1174; 1238; 1302; 1410; 1502. MS (HRMS):
found: m/z 632.9881 [M]+; C25H17NO6SF5Br; calculated: 632.9875.
1H NMR (300 MHz, DMSO-d6), δ: 2.80—2.97 (m, 2 H, H(5),
H(13)); 3.16—3.28 (m, 1 H, H(5)), 3.45—3.56 (m, 1 H, H(6));
3.62 (s, 3 H, OCH3); 3.70—4.02 (m, 2 H, H(6), H(13));
4.53—4.88 (m, 3 H, 2 H(8), H(13a)); 6.04 (d, 2 H, OCH2O,
J = 9.0 Hz); 6.84 (s, 1 H, H(4)); 7.15 (s, 1 H, H(1)); 7.58 (s, 1 H,
H(11)); 11.51 (br.s, 1 H, NH+). 19F NMR (282 MHz, DMSO-d6),
δ: 4.0 (m, 2 F, F(3´), F(5´)), 21.1 (br.t, 1 F, F(4´), J = 21 Hz);
26.6 (m, 2 F, F(2´), F(6´)). 13C NMR (75 MHz, DMSO-d6), δ:
25.44 (C(5)), 34.11 (C(13)), 49.47 (C(6)*), 50.02 (C(8)*), 56.65
(OCH3), 58.55 (C(13a)), 101.35 (OCH2O), 105.61 (C(1)), 108.33
(C(4)), 112.60 (C(1´)), 117.17 (C(11)), 123.57 (C(12)), 124.78,
125.09, 125.40 (C(8a)**, C(13b)**, C(4a)**), 126.15 (C(12a),
133.79 (C(9)), 137.75 (d, C(2´), C(6´), 1J = 252 Hz), 144.36 (d,
C(3´), C(5´), 1J = 260 Hz), 144.99 (d, C(4´), J = 258 Hz),
1
146.71, 147.01 (C(2), C(3)), 149.99 (C(10)).
12-Bromotetrahydroberberrubine 9-O-(2´,3´,5´,6´-tetrafluoro-
benzene)sulfonate hydrobromide (14b). Yield 56%. M.p. 243.4 °C
(decomp.). Found (%): C, 43.80; H, 2.80; N, 2.15; S, 4.76;
F, 11.44; Br, 23.50. C25H18NO6SF4Br•HBr. Calculated (%):
C, 43.06; H, 2.75; N, 2.01; S, 4.60; F, 10.90; Br, 22.92. UV (EtOH),
12-Bromotetrahydroberberrubine 9-O-ethylsulfonate (14e).
Yield 54%. M.p. 195.5 °C (decomp.). Found (%): C, 50.70; H, 4.26;
N, 2.84; S, 6.51; Br, 16.12. C21H22NO6SBr. Calculated (%):

Synthesis of tetrahydroberberrubine sulfonates
Russ. Chem. Bull., Int. Ed., Vol. 68, No. 5, May, 2019
1059
C, 50.81; H, 4.47; N, 2.82; S, 6.46; Br, 16.10. UV (EtOH),
λmax/nm: 204; 289. IR (KBr), ν/cm–1: 1228; 1363; 1483. MS
(HRMS): found: m/z 495.0337 [M]+; C21H22NO6SBr; calcu-
(s, 3 H, ArCH3); 2.58—2.62 (m, 1 H, H(5)); 2.81—2.90 (m, 1 H,
H(5)); 2.94—2.98 (m, 1 H, H(6)); 3.26—3.31 (m, 1 H, H(13));
3.34—3.37 (m, 1 H, H(8)); 3.42—3.44 (m, 1 H, H(13a)); 3.47
(s, 3 H, OCH3); 3.94 (m, 1 H, H(8), J = 16 Hz); 5.94—5.97
(m, 2 H, OCH2O); 6.68 (s, 1 H, H(4)); 6.94 (s, 1 H, H(1)); 7.26
(s, 1 H, H(11)); 7.51 (d, 2 H, H(3´), H(5´), J = 8 Hz); 7.82
(d, 2 H, H(2´), H(6´), J = 8 Hz). 13C NMR (100 MHz, DMSO-d6),
δ: 21.50 (CH3), 29.15 (C(5)), 37.21 (C(13)), 50.10 (C(6)),
53.78 (C(8)), 56.24 (OCH3), 58.87 (C(13a)), 100.97 OCH2O),
106.02 (C(1)), 108.48 (C(4)), 115.29 (C(11)), 122.80 (C(12)),
127.32 (C(12a), 127.63 (C(4a)), 128.38 (C(2´), C(6´)), 130.20
(C(3)´, C(5´), 130.57 (C(8a)), 132.41 (C(13b)), 133.60 (C(1´)),
134.47 (C(9)), 145.90 (C(4´)), 145.95, 146.09 (C(2), C(3)),
150.42 (C(10)).
1
lated: 495.0346. H NMR (400 MHz, CDCl3), δ: 1.56 (t, 3 H,
CH3, J = 8 Hz); 2.54—2.69 (m, 3 H, H(5), H(6), H(13));
2.98—3.29 (m, 3 H, H(5), H(6), H(13)); 3.38—3.52 (m, 2 H,
CH2SO2O); 3.53—3.58 (m, 1 H, H(13a)); 3.65 (d, 1 H, H(8),
J = 16 Hz); 3.83 (s, 3 H, OCH3); 4.24 (d, 1 H, H(8), J = 16 Hz);
5.91 (s, 2 H, OCH2O); 6.57 (s, 1 H, H(4)); 6.75 (s, 1 H, H(1));
7.08 (s, 1 H, H(11)). 13C NMR (100 MHz, CDCl3), δ: 8.23 (CH3),
29.30 (C(5)), 37.31 (C(13)), 47.35 (C(6)), 50.60 (CH2SO2O*),
54.00 (C(8)*), 56.07 (OCH3), 59.07 (C(13a)), 100.70 (OCH2O),
105.41 (C(1)), 108.30 (C(4)), 114.64 (C(11)), 122.70 (C(12)),
127.52 (C(8a)**), 127.80 (C(13b**), 130.06 (C(4a)**), 132.76
(C(12a), 134.56 (C(9)), 145.94, 146.06 (C(2), C(3)), 149.67 (C(10)).
12-Bromotetrahydroberberrubine 9-O-propylsulfonate (14f).
Yield 32%. M.p. 190.2 °C (decomp.). UV (EtOH), λmax/nm:
205; 289. IR (KBr), ν/cm–1: 1228; 1367; 1483. MS (HRMS):
found: m/z 509.0510 [M]+; C22H24NO6BrS; calculated: 509.0502.
1H NMR (400 MHz, CDCl3), δ: 1.02 (t, 3 H, CH3CH2, J = 8 Hz);
2.99—2.11 (m, 3 H, CH3CH2); 2.55—2.70 (m, 3 H, H(5), H(6),
H(13)); 2.99—3.29 (m, 3 H, H(5), H(6), H(13)); 3.34—3.48 (m,
2 H, CH2SO2O); 3.52—3.60 (m, 1 H, H(13a)); 3.66 (d, 1 H,
H(8), J = 16 Hz); 3.84 (s, 3 H, OCH3); 4.24 (d, 1 H, H(8),
J = 16 Hz); 5.91 (s, 2 H, OCH2O); 6.57 (s, 1 H, H(4)); 6.75
(s, 1 H, H(1)); 7.08 (s, 1 H, H(11)). 13C NMR (100 MHz, CDCl3),
δ: 12.89 (CH3CH2), 17.34 (CH3CH2), 29.24 (C(5)), 37.25
(C(13)), 50.60 (C(6)), 53.98 (C(8)*), 54.34 (CH2SO2O*), 56.10
(OCH3), 59.08 (C(13a)), 100.72 (OCH2O), 105.41 (C(1)), 108.31
(C(4)), 114.69 (C(11)), 122.69 (C(12)), 127.48 (C(8a)**), 127.74
(C(13b)**), 129.98 (C(4a)**), 132.65 (C(12a), 134.56 (C(9)),
145.97, 146.08 (C(2), C(3)), 149.70 (C(10)).
12-Bromotetrahydroberberrubine 9-O-butylsulfonate (14g).
Yield 74%. M.p. 116.9 °C (decomp.). Found (%): C, 52.00;
H, 4.73; N, 2.76; S, 6.66; Br, 16.04. C23H26NO6SBr. Calculat-
ed (%): C, 52.68; H, 5.00; N, 2.67; S, 6.11; Br, 15.24. UV (EtOH),
λmax/nm: 205; 289. IR (KBr), ν/cm–1: 1228; 1290; 1369; 1483.
MS (HRMS): found: m/z 523.0652 [M]+; C23H26NO6SBr;
calculated: 523.0659. 1H NMR (400 MHz, CDCl3). δ: 0.98
(t, 3 H, CH3CH2, J = 8 Hz); 1.47—1.57 (m, 3 H, CH3CH2);
1.94—2.06 (m, 2 H, CH3CH2CH2); 2.55—2.70 (m, 3 H, H(5),
H(6), H(13)); 2.99—3.29 (m, 3 H, H(5), H(6), H(13)); 3.33—3.48
(m, 2 H, CH2SO2O); 3.53—3.60 (m, 1 H, H(13a)); 3.62—3.69
(d, 1 H, H(8), J = 16 Hz); 3.84 (s, 3 H, OCH3); 4.24 (d, 1 H,
H(8), J = 16 Hz); 5.91 (s, 2 H, OCH2O); 6.57 (s, 1 H, H(4));
6.75 (s, 1 H, H(1)); 7.08 (s, 1 H, H(11)). 13C NMR (100 MHz,
CDCl3), δ: 13.39 (CH3CH2), 21.44 (CH3CH2), 25.43 (CH3-
CH2CH2), 29.27 (C(5)), 37.28 (C(13)), 50.61 (C(6)), 52.48
(CH2SO2O*), 54.00 (C(8)*), 56.09 (OCH3), 59.08 (C(13a)),
100.72 (OCH2O), 105.42 (C(1)), 108.32 (C(4)), 114.69 (C(11)),
122.68 (C(12)), 127.51 (C(8a)**), 127.78 (C(13b)**), 130.02
(C(4a)**), 132.71 (C(12a), 134.60 (C(9)), 145.98, 146.08 (C(2),
C(3)), 149.71 (C(10)).
Biological assays were performed in CD-1 mice with a body
weight of 25—35 g. The animals were obtained from the vivarium
of the Institute of Cytology and Genetics of the Siberian Branch
of the Russian Academy of Sciences, where they were housed
under standard vivarium conditions and had ad libitum access to
water and standard granulated food. After the quarantine, the
animals were randomized by weight into groups containing eight
mice of the same sex per group. All manipulations on animals
were carried out in strict compliance with the legislation of the
Russian Federation (Order No. 708 N of the Ministry of Health
of the Russian Federation, August 28, 2010, GOST 33044-2014
"Principles of Good Laboratory Practice") and in accordance
with the European Convention for the Protection of Vertebrate
Animals used for Experimental and other Scientific Purposes
(Strasbourg, 1986).
Mouse model of acute experimental hyperlipidemia induced by
the detergent Triton WR 1339. Sulfonates 13a—g and 14a—h or
Simvastatin (as a positive control) were mixed with several drops
of Tween-80 and then distilled water was added. The resulting
suspension was orally administered to mice once a day for four
days in a volume of 0.2 mL/10 g of body weight at a dose of
100 mg kg–1 for the sulfonates and at a dose of 40 mg kg–1 for
Simvastatin.
One hour after the last (fourth) administration, all animals
were intraperitoneally injected with a 7% Triton WR1339
(Tyloxapol, CAS 25301-02-4, Sigma) solution in a volume of
0.1 mL per 10 g of body weight. Then the mice were deprived of
food and sacrificed 24 h after the administration of Triton. The
blood was collected from neck vessels and centrifuged for 15 min
at 3000 rpm to prepare the serum. The concentration of total
cholesterol and triglycerides in the blood was determined using
the standard diagnostic kit (Olvex-diagnosticum) on a StatFax
3300 spectrophotometer (USA).
Antibacterial and antifungal activity. The screening of anti-
bacterial and antifungal activity was performed by the CO-ADD
using whole cell growth inhibition assays. The tested compounds
were predissolved in DMSO so that their concentration was
10 mg mL–1. Then the solutions were diluted with water to the
32 μg mL–1 concentration of the tested compounds. Two portions
of each sample with a volume of 5 μL were placed in a 384-well
plate (Corning 3640) and then bacterial cells were added. The
bacteria were cultured in CAMHB medium (Cation-adjusted
Mueller Hinton broth) at 37 °C for 16 h, diluted in fresh CAMHB,
and incubated at 37 °C. The bacterial cultures from the middle
phase were diluted to the cell density of 5•105 CFU mL–1 (the
absorbance was determined at a wavelength of 600 nm, OD600),
and a portion (45 μL) of this solution was added to each well of
12-Bromotetrahydroberberrubine 9-O-(4´-toluene)sulfonate
(14h). Yield 67%. M.p. 170.1 °C (decomp.). Found (%): C, 55.59;
H, 4.39; N, 2.81; S, 6.13; Br, 14.19. C26H24NO6SBr. Calculat-
ed (%): C, 55.92; H, 4.33; N, 2.51; S, 5.74; Br, 14.31. UV (EtOH),
λmax/nm: 290. IR (KBr), ν/cm–1: 1171; 1228; 1298; 1365; 1485.
MS (HRMS): found: m/z 556.0427 [M – H]+; C26H23NO6SBr;
calculated: 556.0424. 1H NMR (400 MHz, DMSO-d6), δ:
2.29—2.36 (m, 1 H, H(6)*); 2.37—2.43 (m, 1 H, H(13)*); 2.45

1060 Russ. Chem. Bull., Int. Ed., Vol. 68, No. 5, May, 2019
Nechepurenko et al.
the plate. The plate was covered and incubated at 37 °C for 18 h
without shaking. The bacterial growth inhibition was determined
by measuring the absorbance at a wavelength of 600 nm using
a Tecan M1000 Pro monochromator-based microplate reader.
The percentage of growth inhibition was calculated for each well
using the negative control (CAMHB medium) and the positive
control (CAMHB medium supplemented with bacteria in the
absence of inhibitors) as the reference in the same plate. All
experiments were run in duplicate.
We thank the Multi-access Chemical Service Center
of the Siberian Branch of the Russian Academy of Sciences
for performing spectroscopic and analytical measurements.
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We are grateful to the Community for Antimicrobial
Drug Discovery (CO-ADD, Australia) for performing
antimicrobial screening. The CO-ADD is financially sup-
ported by the Wellcome Trust (UK) and the University of
Queensland (Australia).
Received January 25, 2019;
in revised form February 25, 2019;
accepted March 22, 2019