Novel, potent, selective and cellular active ABC type PTP1B inhibitors containing (methanesulfonyl-phenyl-amino)-acetic acid methyl ester phosphotyrosine mimetic

Article abstract of DOI:10.1016/j.bmc.2015.09.024

Protein tyrosine phosphatase 1B (PTP1B) which plays an important role in the negative regulation of insulin and leptin pathway has emerged as a novel promising therapeutic target for the treatment of type 2 diabetes mellitus and obesity. Upon careful study, a series of novel scaffold and simple synthesis method inhibitors were discovered based on the analysis of X-ray crystal structures of PTP1B/inhibitor complexes and docking simulations. Among them, compound P7 exhibited high inhibitory activity (IC₅₀ = 222 nM) with moderate selectivity (8-fold) over T-cell PTPase (TCPTP) through interacting with the A, B and C binding sites of PTP1B enzyme. Further studies on cellular activities revealed that compound P7 could enhance insulin-mediated IRβ phosphorylation and insulin-stimulated glucose uptake.

Full text of DOI:10.1016/j.bmc.2015.09.024

Accepted Manuscript
Novel, Potent, Selective and Cellular Active ABC Type PTP1B Inhibitors Con-
taining (Methanesulfonyl-phenyl-amino)-acetic acid methyl ester Phosphotyr-
osine Mimetic
Peihong Liu, Yongli Du, Jingkang Shen, Qunyi Li
PII:
S0968-0896(15)30049-3
DOI:
http://dx.doi.org/10.1016/j.bmc.2015.09.024
BMC 12571
Reference:
To appear in:
Bioorganic & Medicinal Chemistry
Received Date:
Revised Date:
Accepted Date:
6 June 2015
29 August 2015
15 September 2015
Please cite this article as: Liu, P., Du, Y., Shen, J., Li, Q., Novel, Potent, Selective and Cellular Active ABC Type
PTP1B Inhibitors Containing (Methanesulfonyl-phenyl-amino)-acetic acid methyl ester Phosphotyrosine Mimetic,
Bioorganic & Medicinal Chemistry (2015), doi: http://dx.doi.org/10.1016/j.bmc.2015.09.024
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Novel, Potent, Selective and Cellular Active ABC
Type PTP1B Inhibitors Containing
Methanesulfonyl-phenyl-amino)-acetic acid methyl
ester Phosphotyrosine Mimetic
(
a,†
a, †,
b
c,
Peihong Liu , Yongli Du *, Jingkang Shen , Qunyi Li *
a
School of Chemistry and Pharmaceutical Engineering, Qilu University of Technology, 3501 Daxue
Road, Jinan 250353, China
b
State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of
Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, P.R. China
c
Clinical Pharmacy Laboratory, Huashan Hospital, Fudan University, 12 Wu Lu Mu Qi M Road,
Shanghai 200040, China
†These two authors contributed equally to this work.
*
To whom correspondences should be addressed. Tel.: +86 531 89631208 (YLD) or 86 21 52889303 (QYL); Fax:
86 0531 89631207 (YLD) or 86 21 52889307 (QYL);
+
E-mail: ylduyjs@163.com or qyli1234@163.com
Abstract:
Protein tyrosine phosphatase1B (PTP1B) which plays an important role in the negative
regulation of insulin and leptin pathway has emerged as a novel promising therapeutic target for the
treatment of type 2 diabetes mellitus and obesity. Upon careful study, a series of novel scaffold and
simple synthesis method inhibitors were discovered based on the analysis of X-ray crystal structures
of PTP1B/inhibitor complexes and docking simulations. Among them, compound P7 exhibited high
inhibitory activity (IC50 = 222 nM) with moderate selectivity (8-fold) over T-cell PTPase (TCPTP)
through interacting with the A, B and C binding sites of PTP1B enzyme. Further studies on cellular
activities revealed that compound P7 could enhance insulin-mediated IRβ phosphorylation and
insulin-stimulated glucose uptake.
Key words

Type 2 diabetes mellitus
. Introduction
Type 2 diabetes mellitus (T2DM) is a multi-cause metabolic diseases resulting from insulin
PTP1B
Inhibitor Structure–activity relationships
1
deficiency and insulin resistance which is associated not only with the conduction disturbance of
signal transduction but also with the aberration of interaction between insulin and insulin receptor
1
(
IR). In insulin signaling pathway of normal individuals, insulin is combined with α subunits of IR
which subsequently is activated resulting in the autophosphorylation of both subunits and IR on
tyrosine residues. Following activation, IR substrate (IRS) is phosphorylated successively and then
the phosphatidylinositol 3 kinase (PI3K)/AKT pathway is activated, while promotes the transcription
and translation of glucose transporters (GLUTs) and guides GLUTs from the cytoplasm to the
2
membrane to promote the uptake of glucose by cells ultimately. However, PTP1B as a negative
regulator for the signaling pathway of insulin and leptin dephosphorylates the phosphorylation of
3
,4
5- 7
8
IR, IRS and Janus kinase 2 (JAK2), which is relevant to the signal transduction of leptin, then
the signal transduction of insulin pathway are blocked resulting in T2DM and obesity on a global
9
scale. The study results of PTP1B knockout mice have demonstrated that mice lacking the PTP1B
1
0, 11
displayed improved insulin sensitivity and resistance to obesity.
Interestingly, gene deletion of
1
2
PTP1B did not affect the normal growth and longevity in mice. Therefore, PTP1B as a novel
promising therapeutic target has become a hot spot of research for the treatment of T2DM and
1
3
obesity.
Accordingly, various higher activities of PTP1B inhibitors have been developed in the last
1
4, 15
16-18
decade.
However, only two inhibitors can do further research into the clinical.
Poor cell
1
9, 20
permeability, low oral bioavailability and weak selectivity for the active site
are the major
reasons of the many previously disclosed PTP1B inhibitors such as compounds 1 and 2 which
respectively contain the bis-anionic on difluoromethyl phosphonates (DFMP) moiety and the
2
1, 22
carboxymethylsalicyclic acids (CMS) moiety with monoacid.

F
F
OH
OH
P
O
OH
O
O
HO
O
O
H
NH
2
N
NH
O
P
O
O
O
O
HO
HO
O
OH
N
H
F
F
OH
NHAc
Compound 1
Compound 2
K
K
i
= 2.4 nM (PTP1B)
K
K
i
= 9.0 µM (PTP1B)
i
= 24 nM (TCPTP)
=182 µM (TCPTP)
i
Figure 1. Structures of reported DFMP moiety (Compound 1) and CMS moiety (Compound 2).
Multiple positively charged sites (A, B, C, D and E) were demonstrated in the PTP1B
2
3
enzyme. The A site is the positively charged catalytic phosphate binding pocket with 9-Å deep
from Cys215 to Phe182) and 10-Å wide (from Tyr46 to Gln262), which contains the catalytic
(
Cys215 in the polar phosphate binding loop (Cys215–Arg221) and hydrophobic residues (Y46, V49,
F182, A217, I219, and Q262) that interact with the aryl ring of phosphotyrosine (pTyr). The B site is
a noncatalytic secondary phosphate binding pocket which is larger (13×20 Å) and shallower (>4 Å)
than the A site and contains several polar and hydrophobic residues. The C site is a large flat region
that can accommodate large negatively charged substituents. The D site is a small pocket that
shielded from solvent and adjacent to the A site, and the E site is a highly solvent exposed region
2
3
located over the flap (Phe182) of the protein. A comprehensive review of the reported PTP1B
inhibitors proposed that the inhibitors which bind in the A site and extend into at least one additional
23
site will improve not only the binding affinity but also the opportunity for selectivity over TCPTP.
More recently, our research group has reported the discovery of N-(2,
-diethoxy-phenyl)-methanesulfonamide based compounds as novel, potent, selective and cellular
5
active ADC type PTP1B inhibitors which interact with the A, D and C site through
2
4
fragment-docking-oriented de novel design.
methanesulfonyl-phenyl-amino)-acetic acid methyl ester analogues as novel potent, selective and
cellular active ABC type PTP1B inhibitors will be reported in details.
In this paper, the discovery of
(
2. Inhibitor Design
In the A site, the structures of these PTP1B inhibitors were purposefully designed based on the
analysis of X-ray crystal structures of DFMP moiety and CMS moiety bounding into the PTP1B
pTyr active site (PDB code 1Q6T). A dense of hydrogen bonds were observed between DFMP
moiety and Phe182, Ser216, Ala217, Tle219, Gly220, Arg221 (Fig. 2a), while the CMS moiety

formed a number of hydrogen bonds with the Lys120, Gly220 and Arg221 (Fig. 2b).
Figure 2. Binding mode of DFMP moiety and CMS moiety to the PTP1B pTyr active site derived from docking
simulations showing respectively in Figure a and b. Carbon is in dark gray for PTP1B and gray for ligands, oxygen
atoms are in red, nitrogen is in blue, sulfur is in yellow, fluorine is in green, phosphorus is in orange and hydrogen
is in cyan. Hydrogen bonds are shown as dashed yellow lines. These images were generated using the Sybyl-x
program.
In order to eliminate the charge while retaining the proton-accepting capability, the neutral
methyl sulfonyl group and methyl acetate group were consolidated into one fragment to replace the

2 3
-CF PO group on DFMP moiety and monoacid group CMS moiety in the A site. The hydrogen bond
acceptors of two sulfonyl oxygens effectively mimic the oxygens of the DFMP moiety, while the
ester group mimics the CMS moiety carboxyl group in the deep A site. The 3D docking model of
fragment 3 to PTP1B was constructed using Surflex-dock docking module within the software Sybyl
X 1.0. (PDB code 1Q6T). The two sulfonyl oxygens and the oxygens of ester group in fragment 3
form a total of six hydrogen bonds with the backbone NHs of Lys120, Ser216, Ala217 at the bottom
of the active site (Fig. 3). Clearly, the fragment 3 is able to achieve most hydrogen-bonding
interactions that the DFMP moiety and CMS moiety make with the active site.
Figure 3. Binding mode of fragment 3 to the PTP1B pTyr active site. This image was generated using the Sybyl-x
program.
Then the chain length was increased to the aryl substituent of fragment 3 to reach further into
23
the B site, which may simultaneously increase the affinity and specificity. Therefore, the sulfamide
were introduced and attempted to interact with the corresponding residues in the B site through van
der waals force, hydrophobic interaction or hydrogen-bond interaction (Fig. 4). Meanwhile, the
2
chain extending to the C site was anticipated. So the R groups were changed to interact with the C
site, which probably had an impact on the inhibitory activity or selectivity (Fig. 4). Consequently,
compound P5-P16 with nitrogen atom at their centers were designed extending to the A, B and C
sites.

O
R
2
OH
S
O
O
N
O
n
R
4
N
S
OH
O
R
3
CMS moiety
bioisosteric
replacement
fragment growing
O
O
S
O
N
O
N
O
S
R
1
O
R
1
O
O
O
F
F
O
P
3
4
HO
OH
R
R
R
R
1
= Me-, Et-
= R OPh-, Bn-, Ph-, R
= Me-, EtOPh-, Bn-
= H-, Bn-, 3-ClBn-, 4-MeBn-
n = 0, 1
2
5
5
= Me-, Et-, Pr-, Bu-
DFMP moiety
3
4
Figure 4. Fragment design and the growth of PTP1B inhibitors.
Synthesis
The general method for the synthesis of P5-P12 is depicted in Scheme 1. Intermediate 5 was
carried out in high yield by the bromination of commercially available 1-methyl-4-nitro-benzene
2
5
with N-bromosuccinimide (NBS), subsequent amination with Gabriel synthesis afforded
26
4
-nitro-benzylamine. Then intermediates 9a-9c were effectively prepared by alkylation of 8 with
27, 28
α-halogenated aromatic hydrocarbons followed by sulfonylation with methanesulfonyl chloride.
29
After nitro reduction, intermediates 9a-9c were converted to 10a-10c in good yield. Subsequent
sulfonylation with benzenesulfonyl chloride or benzylsulfonyl chloride or benzenesulfonyl chloride
3
0
derivatives afforded intermediates 13a-13h. The benzenesulfonyl chloride derivatives (12) were
31, 32
synthesized by alkylation of phenol and of later sulphonation with chlorosulfonic acid.
Then
substitution reaction with 16a-16b which was obtained by bromination with NBS followed by
sulfonylation of 4-methylaniline with alkylsulfonyl chloride and alkylation of 14a-14b with methyl
bromoacetate separately provided compounds P5-P12. Compounds P13, P14 were prepared in a
similar manner followed by sulfonylation, alkylation, nitro reduction, sulfamide formation and
alkylation in scheme 2. Compounds P15, P16 were also carried out according to the steps of scheme
1
3
followed by the formation of sulfonamide, alkylation, nitro reduction and sulfonylation in scheme
.

O
Br
N
NH2
O
a
b
c
d
NO
2
NO
2
NO2
NO2
5
6
7
O
O
O
O
O
O
S
S
S
NH
N
R4
N R
4
e
f
O
O
S
NO
2
NO
2
NH
2
N
R
4
8
9a-9c
10a-10c
l
R
5
R
5
O
OH
O
O
R2
g
NH
O
S
h
S
O
R
2
N
R4
O
N
S
O
S
O
m
O
1
3a-13h
Cl
O
O
S
1
1a-11d
12a-12d
O
N
R
1
Br
O
i
O
j
k
P5 R
1 2 4
= Me-, R = Ph-, R = Bn-
O
O
P6 R1 = Me-, R2 = R OPh-, R5 = Me-, R4 = Bn-
P7 R
P8 R1 = Me-, R2 = R OPh-, R5 = Pr-, R4 = Bn-
5
P9 R1 = Me-, R2 = R OPh-, R5 = Bu-, R4 = Bn-
P10 R
P11 R
P12 R
5
N
O
S
O
O
NH
2
HN
N
O
S
1 2 5 5 4
= Me-, R = R OPh-, R = Et-, R = Bn-
R
1
R1
S
R1
5
O
O
O
O
1
1
1
= Me-, R
= Me-, R
= Et-, R = Bn-, R = 3-ClBn-
2 4
2
= Bn-, R
= Bn-, R
4
= Bn-
= 4-MeBn-
14a- 14b
1
5a- 15b
16a- 16b
2
4
Scheme 1.(a) NBS, BPO, CCl
·H O, methanol, reflux, 60°C, 3 h; (d) C
·6H O; NaBH , methanol, 0°C, 30 min; (g) R
CO , DMF, refluxed, 60-70°C, 5 h; (h) chlorosulfonic acid, DCM, 0°C, 2 h; (i) C
methyl bromoacetate, NaH, DMF, N , rt, 12 h; (k) NBS, AIBN, CCl , reflux, 80°C, 10 h; (l) C
, rt, overnight; (m) KI, K CO , DMF, rt, overnight.
4
, reflux, 75°C,10 h; (b) phthalimide potassium, TBAB, DMF, reflux, 100°C, 5 h; (c)
N
2
H
4
2
5
H
5
N, DCM , N
2
, 0°C, 20 min; (e) DMF, K
2
3
CO , rt, 60-70°C, 3 h; (f)
o
NiCl
2
2
4
5
= Me, KOH, DMS, methanol, 0-60 C, 5 h; R
5
= Et, Pr, Bu
, rt, 12 h; (j)
K
2
3
5
H
5
N, DCM, N
2
2
4
5 5
H N, DMAP, DCM,
N
2
2
3
NO
2
NO
2
NO
2
NH
2
a
b
c
O
S
O
S
O
O
S
O
O
N
R
N
NH
H
2
N
4
R
4
1
9a R
4
= Bn-
1
7
4
18a R = Bn-
19b R4 = 3-ClBn-
1
8b R4 =3-ClBn-
O
H
N
O
O
S
N
S
O
d
e
O
O
S
R
4
O
R1
N
N
O
S
N
R
S
O
O
4
O
O
2
2
0a R
0b R
4
= Bn-
=3-ClBn-
P13 R
P14 R
= Me-, R
= Me-, R
= Bn-
= 3-ClBn-
1
1
4
4
4
Scheme 2. (a) C
5
H
5
N, DCM, N
2
, rt, overnight; (b) DMF, K
2
CO
3
2 2 4
, rt, 3 h; (c) NiCl ·6H O; NaBH , methanol, 0°C,
3
0 min; (d) C
5
H
5
N, DMAP, DCM, N
2
, rt, overnight; (e) KI, K
2
CO
3
, DMF, rt, overnight.

O
O
N
S
R
2
2
NO
2
NO
2
O
O
S
a
b
N
O
O
NH
O
H
2
N
S
R
2
NO
O
2
1a R
2
= Bn-
= 4-BuOPh-
22a R
22b R
2
= Bn-
21b R
2
2
= 4-BuOPh-
O
O
O
O
S
R2
S
R2
N
c
N
d
O
O
O
O
O
S
S
O
S
N
N
O
HN
O
NH
R
3
2
O
O
2
2
3a R
3b R
2
= Bn-
= 4BuOPh-
P15 R
P16 R
2
= Bn-,R
= 4-BuOPh-, R
3
= EtOPh-
= Bn-
2
2
3
Scheme 3.(a) C
5
H
5
N, DMAP, DCM, N
2
, rt, overnight; (b) KI, K
, rt, overnight.
2 3 2 2 4
CO , DMF, rt, overnight; (c) NiCl ·6H O, NaBH ,
methanol, 0°C; 30 min; (d) C
5
H
5
N, DCM, N
2
4
. Results and discussion
.1. PTP1B enzyme inhibitory activity and structure–activity relationship
All the synthesized compounds were evaluated for inhibitory intensity against PTP1B
4
3
3, 34
enzyme,
and the results were shown in Table 1. According to evaluation results, we analyzed the
preliminary structure–activity relationships. Compounds P10 (n = 1) and P12 (n = 1) showed no
inhibitory activity when benzyl group and 3-chlorobenzyl were respectively introduced to R
4
and
was
compounds P11 (n = 1, IC50 = 20338 nM) was almost no inhibitory activity when R
4
4
-methylbenzyl. Excitingly, compared to compound P10, the removal of methylene in compound
P13 (n = 0) led to a significant increase in inhibitory potency with IC50 of 492 nM. Conversely, the
potency was lost when 3-chlorobenzyl was introduced at R (P14, n = 0). Among P10-P14,
4
compound P13 (n=0) exhibited excellent inhibitory activity, perhaps because the relatively small
volume structure (n = 0, with nothing substituent in B site) provided a preferred conformation
adapted to the B site, while the volume of compounds P10-P12 (n = 1) and compound P14 (n = 0,
with chloric substituent in B site) in B site were too large and difficult to adapt to the size of the
pocket when R
level of inhibitory activity (IC50 = 470 nM) when R
and hydrogen respectively compared with compound P13. However, compared to compound P15,
-fold decrease of inhibitory potency was observed when R , R and R were 4-butoxy-phenyl,
2
were all the flexible and bulky benzyl. Compound P15 (n = 0) exhibited the same
1
, R and R were ethyl-, 4-ethoxy-phenyl groups
3
4
4
2
3
4
benzylsulfonylamino groups and hydrogen respectively in compound P16 (n = 0, IC50 = 1709 nM).
Interestingly, compound P9 (n = 1, IC50 = 896 nM) displayed 2-fold more potent than compound

P16 although with the same substitute at R
group in B site may be not obvious and n=1 was more suitable for B site when R
-butoxy-phenyl group instead of benzyl group. Compound P8 (n = 1, IC50 = 902 nM) displayed the
same level of inhibitory activity compared with compound P9 when the 4-propoxy-phenyl was
introduced to R . Excitingly, the inhibitory activity was dramatically increased and displayed 4- fold
more potent than compound P8 when the 4-ethoxy-phenyl was introduced to R (P7, n = 1, IC50
22 nM). Conversely, the introduction of 4-methoxy - phenyl (P6, n = 1, IC50 = 346 nM) or phenyl
group (P5, n = 1, IC50 = 16098 nM) to the same position respectively resulted in about 1.5-fold and
2-fold decrease of inhibitory potency than compound P7. Hence, compounds P5-P9 demonstrated a
large volume structure (n = 1) in B site with 4-ethoxy-pheny at R provided a preferred conformation
2
. That demonstrated the positive role of methylsulfonyl
2
was
4
2
2
=
2
7
2
adapted to the pockets of B and C. According to the shape characteristics of PTP1B pockets,
compound P5-P16 indicated that the shape and length of whole structure from B to C site played a
very important role in inhibitory activity of compounds based on the steady binding affinity of
structure in the A site. Among them, compound P7 with the optimum configuration was a novel
promising lead compound.
a
Table1. Inhibitory activity of compounds P5-P16 against PTP1B
O
R
2
S
O
N
R
4
n
N
S
O
R
3
O
O
S
O
N
R
1
O
O
P5 - P16
NO.
n
R
1
R
2
R
3
R
4
IC50 (nM)
mean ± SEM
16098 ± 3954
346 ± 98
P5
P6
1
1
1
1
1
1
1
1
0
Me-
Me-
Me-
Me-
Me-
Me-
Me-
Et-
Ph-
Me-
Me-
Me-
Me-
Me-
Me-
Me-
Me-
Me-
Bn-
Bn-
4-MeOPh-
4-EtOPh-
4-n-PrOPh-
4-n-BuOPh-
Bn-
P7
Bn-
222 ± 53
P8
Bn-
902 ± 105
896 ± 46
P9
Bn-
b
P10
P11
P12
P13
Bn-
NA
Bn-
4-MeBn-
3-ClBn-
Bn-
20338 ± 724
NA
Bn-
Me-
Bn-
492 ± 106

P14
P15
P16
0
0
0
Me-
Et-
Bn-
Bn-
Me-
EtOPh-
Bn-
3-ClBn-
NA
H
H
470 ± 146
1709 ± 625
Et-
4-n-BuOPh-
a
Values represent triplicate determinations.
b
NA: Inhibition rate <50% at 25 µM concentration.
4
.2. The selectivity of compounds P6, P7, P13 and P15 over TCPTP, SHP-1, SHP-2, LAR
Subsequently, the potent active compounds P6, P7, P13 and P15 with IC50 below 1μM were
selected to test against other PTPs (TCPTP, SHP-1, SHP-2 and LAR). As shown in Table 2,
compound P6 displayed no enzyme inhibitory activities against other PTPs. Similarly, no inhibition
of SHP2 and LAR was observed in compound P7 with 8-fold and 10-fold selectivity for PTP1B over
TCPTP and SHP1. Compound P13 exhibited about 20-fold PTP1B selectivity than for SHP1 and
SHP2, and showed no inhibition for TCPTP and LAR, while compound P15 showed about 2-fold
decreased selectivity than compound P7 for TCPTP, but 2-fold increased selectivity for SHP1.
Table 2.The inhibitory activity of select compounds P6, P7, P13, P15 as PTP1B inhibitors against a panel of PTPs,
a
IC50
Compound
PTP1B
nM）
TCPTP
SHP1
SHP2
LAR
（
（nM）
（nM）
（nM）
（nM）
oleanolic acid 153 6 ± 267 5460 ± 740
Na VO
3
4
14190 ± 2630 11620 ± 2840 22310 ± 4670
b
P6
P7
346 ± 98
222 ± 53
492 ± 106
NA
NA
NA
NA
NA
NA
NA
NA
1860 ± 270
NA
2310 ± 440
P13
P15
9610 ± 1350 11640 ± 2190
NA
470 ± 146 1920 ± 260 11360 ± 1870
a
The pNPP assay. IC50 values were determined by regression analysis and expressed as means ± SD of three
replications.
b
NA: Inhibition rate <50% at 25 μM concentration.
4.3. The cellular activity of compound P7
Previous studies have suggested a pivotal role for the intrinsic tyrosine kinase activity of the
IRβ in insulin-mediated signalling cascades.35 PTP1B participates in the dephosphorylation and
inactivation of IR, thus attenuating insulin signaling.34 It has been verified that inhibition of PTP1B

by specific antisense oligonucleotide36 or inhibitors results in improvement of hyperglycaemia and
insulin sensitivity in diabetic animal models.37, 38 Thus, we evaluated the effects of compound P7
on phosphorylation level of IRβ both in CHO cells transfected with hIRβ-expressing plasmid (Figure
5A) and in 3T3-L1 preadipocytes (Figure 5B). As shown in Figures 5A and 5B, compound P7
enhanced insulin-mediated IRβ phosphorylation at concentrations of 15 μM and 30 μM.
5
A
compound P7 (μM)
NC PC 5 15 30
PY-20
β-actin
5
B
compound P7 (μM)
NC PC 15 30
p-IRβ
IRβ
Figure 5A and 5B. Effect of compound P7 on tyrosine phosphorylation of insulin receptor β (IRβ) in CHO cells
transfected with hIRβ-expressing plasmid (5A) or in 3T3-L1 cells (5B). NC, negative control; PC, positive control.
It has been suggested that PTP1B inhibition results in a marked improvement in insulin
38
sensitivity and glucose tolerance, we investigated whether the PTP1B inhibition exerted by P7 also
results in enhanced insulin-stimulated glucose uptake. As shown in Figure 6A, insulin-stimulated
glucose uptake was significantly increased in L6 myotubes treated with P7, and this increase was
2
3.3% and 29.3% at 5 and 10 μM , respectively. Furthermore, P7 also enhanced insulin-stimulated
glucose uptake in human skeletal muscle cells (HSkMC) in a dose-dependent manner (Figure 6B).

6
A
6
B
Figure 6A and 6B. Effects of compound P7 on insulin-stimulated glucose uptake in L6 myotubes (6A) or in
human skeletal muscle cells (HSkMC). 6A, L6 cells or 6B, HSkMC were serum starved for 2 h and then incubated
with varying concentration of compound P7 (0, 1, 5 and 10 µM). After 4 h, insulin (10 nM) stimulated glucose
uptake was evaluated using 2-NBDG as described in Methods. Values are presented as mean ± SEM. n = 4.
#
∗∗∗
P<0.05 vs the control group; P<0.001 vs the insulin-treated group.
4
.4. Molecular docking models
Finally, we obtained the binding mode of the compound P7 based on the docking simulation
(
PDB code 1Q6T). The model of compound P7 showing in Figure 7 revealed that a dense network
of hydrogen bonds are formed between the –N (CH COOCH ) SO CH group and the backbone
2
3
2
3
NHs of Lys120, Ser216, Ala217 and Arg221 at the active site of PTP1B as well as hydrogen-bond
interactions between oxygen atoms of alkoxy group and Arg47. In addition, hydrophobic and π-π

stacking interactions are formed between the phenyl ring of the ligand and the surrounding amino
acid side chains. Due to these multiple interactions, compound P7 effectively combined with the
pockets to serve as a potent inhibitor.
Figure 7. Binding model of compound P7 to PTP1B. Carbon is in green for PTP1B and yellow for compound P7,
oxygen atoms are in red, nitrogen is in blue, sulfur is in yellow. Hydrogen bonds are depicted with red dashes. This
structure figure was prepared using PyMol.
5
. Conclusion
In summary, the novel scaffold and simple synthesis method inhibitors were designed and
synthesized and their biological properties were evaluated. The SAR studies of R -R substituents of
1
4
the chemical formula 4 revealed that six representative compounds (P6, P7, P8, P9, P13, P15)
showed excellent inhibitory activity with IC50 values less than 1 μM. Among them, P6, P7, P13, P15
were selected to investigate the selectivity demonstrated moderate selectivity over TCPTP. More
importantly, compound P7 exhibited high inhibitory activity (IC50 = 222 nM) with 8-fold selectivity
over TCPTP through interacting with the A, B and C binding sites of PTP1B enzyme. Further studies
on cellular activities revealed that compound P7 could enhance insulin-mediated IRβ
phosphorylation and insulin-stimulated glucose uptake. These novel compounds reported in this
study could provide us a possible opportunity for further optimizing to design more potent and
selective ABC type PTP1B inhibitors in future studies.

6. Experimental section
6.1. General synthetic methods
1
Reactions were monitored by thin-layer chromatography (TLC) on silica gel plates . H (400
1
3
MHz) NMR and C (101 MHz) NMR spectra were recorded on a Bruker AVANCE II Fourier
transform spectrometer. The chemical shifts were given in δ (ppm) refer to the signal of CDCl (δ
3
1
13
1
13
7
3 2
.26, H NMR and δ 77.16, C NMR) and the signal of (CD ) SO (δ 2.54, H NMR and δ 39.52, C
NMR). Elemental analyses were performed on a Der C, H, N, O, S Elementar Analysen-
systemeVario EL III.
Unless stated otherwise, Most of the chemicals and reagents used were of AR grade and were
purchased from commercial suppliers without further purification. The solvents used were all AR
grade and were redistilled in the presence of proper desiccant when necessary.
6.1.1. [(4-Bromomethyl-phenyl)-methanesulfonyl-amino]-acetic acid methyl ester (16a)
Methanesulfonyl chloride (3.41 mL, 44 mmol) was added dropwise to p-toluidine (4.28 g, 40
mmol) and pyridine (3.54 mL, 44 mmol) in DCM (50 mL) at 0°C under nitrogen. After addition, the
mixture was warmed to room temperature and stirred overnight. The reaction was quenched with
NaOH (6 mol/L) and enough water added to dissolve the resultant anion. The layers were separated
and the aqueous layer washed with DCM (20 mL). The aqueous layer was cooled (0°C) and
acidified to pH 2.0 by using 18% aqueous HCl. The product precipitates were filtered and washed
with cold water and air-dried to constant weight to afford 4.68 g of 14a (57%) as a colorless solid.
The reaction mixture of 14a (4.26 g, 23 mmol) and suspension of NaH (722 mg, 30 mmol) in
DMF (10 mL) was stirred at 0°C for 45 min. Then methyl bromoacetate (3 mL, 32.4 mmol) was
added and allowed to warm to room temperature with stirring overnight. The solids were removed
by filtration and washed with ethyl acetate (200 mL). The filtrate was washed with saturated brine.
And the organic phase was concentrated under vacuum to afford the yellow oily liquid. Then
purified using flash chromatography. Clean product fractions and mixed fractions eluted. The
product fractions were combined and concentrated under vacuum to afford 5.22 g (88%) of 15a as a
white solid.
NBS (3.98 g, 22.4 mmol) and AIBN (50 mg) were added to a solution of 15a (5.22 g, 20.3
4 2
mmol) in CCl (50 mL) at room temperature. The mixture was thoroughly purged with N before the

addition of AIBN to remove H
2 2
O and O . The solution was stirred at 76°C under nitrogen for 10 h.
The solution was filtered and the precipitate was washed with a little CCl
4
. The combined filtrate
was reduced in volume to give a light yellow liquid. Then purified using flash chromatography.
Clean product fractions and mixed fractions eluted. The product fractions were combined and
1
concentrated under vacuum to afford 4.77 g (70%) of 16a as a white solid. H NMR (400 MHz,
DMSO-d
.1.2. N-(4-Nitro-benzyl)-methanesulfonamide (8)
According to the same procedure described for 15a to 16a, 4-nitrotoluene (15 g, 110 mmol) was
6
,) δ 7.52 – 7.38 (m, 4H), 4.70 (s, 2H), 4.54 (m, 2H), 3.63 (s, 3H), 3.14 – 3.05 (m, 3H).
6
treated with NBS (19.58 g, 110 mmol）and benzoyl peroxide to afford 15.68 g (66%) of 5 as a light
yellow solid. The reaction mixture of 5 (10 g, 46.3 mmol), potassium phthalimide (11.11 g, 60 mmol)
and TBAB (50 mg, 0.16 mmol) in DMF (30 mL) was stirred at 76°C for 5 hours. The samples were
withdrawn at different time intervals and analyzed using TLC until the reaction was completed. Then
the reaction was quenched and cooled to room temperature. The solids were removed by filtration
and washed with ethyl acetate (140 mL). The filtrate was washed with saturated brine, and the
organic phase was concentrated under vacuum to afford 9.80 g (75%) of the yellow solid 6.
The reaction mixture of 6 (9.82 g, 34.8 mmol) and hydrazine hydrate (6.7 mL) in methanol (50
mL) was stirred at 60°C for 3 h. The solvent was evaporated under vacuum and the residue dissolved
in DCM (50 mL). The solution was extracted with (1 mol/L) NaOH (50 mL) and the organic layer
2 4
was dried with Na SO and concentrate in vacuum. The residue was purified by flash
chromatography to afford 3.96 g (75%) of 7. According to the same procedure described for 14,
methanesulfonyl chloride (2.25 mL, 29 mmol) was treated with 7 (3.96 g, 26 mmol) to afford 4.80 g
1
(
80%) of 8 as a yellow solid. H NMR (400 MHz, DMSO-d
6
) δ 8.22 (d, J = 8.4 Hz, 2H), 7.78 (t, J =
6
.0 Hz, 1H), 7.61 (d, J = 8.0 Hz, 2H), 4.30 (d, J = 6.4 Hz, 2H), 2.92 (s, 3H).
.1.3. ({4-[(Benzenesulfonyl-{4-[(benzyl-methanesulfonyl-amino)-methyl]-phenyl}-amino)-met
6
hyl]-phenyl}-methanesulfonyl-amino)-acetic acid methyl ester (P5)
To a stirred solution of 8 (500 mg, 2.17 mmol) in DMF (12 mL) at ambient temperature was
added benzyl bromide (0.31 mL, 2.61 mmol) and potassium carbonate (600 mg, 4.34 mmol) at room
temperature. After 3 h, the reaction mixture was filtrated and washed with ethyl acetate (140 mL).
2 4
The filtrate was washed with saturated brine and dried over anhydrous Na SO and the organic phase

was concentrated under vacuum to afford the yellow solid. Then the resulting solid was
recrystallized from ethanol and the pale yellow crystals 9a were removed by filtration (523 mg,
75%).
NaBH
618 mg, 2.6 mmol) and methanol at 0°C. The whole was stirred at room temperature for 30 min.
After removal of methanol, the reaction mixture was acidified to pH 2.0 by using 10% aqueous HCl.
It was then made basic with a 28% NH aqueous solution and extracted with ethyl acetate. The
organic layer was washed with saturated brine solution and dried over anhydrous Na SO . After
removal of the solvent, further purification was done by column chromatography to give 399 mg
92%) of 10a.
4
(197 mg, 5.2 mmol) was added to a mixture of 9a (481 mg, 1.5 mmol), NiCl
2
2
·6H O
(
3
2
4
(
Pyridine (73 μL, 0.90 mmol) and DMAP were added to a solution 10a (203 mg, 0.7 mmol) in
anhydrous DCM (10 mL). Then benzenesulfonyl chloride (145 mg, 0.76 mmol) was dissolved in
DCM and added dropwise under a nitrogen atmosphere. The reaction mixture was then stirred at
room temperature for 1 days. Whereupon, HCl (1mol/ L) was added and the reaction mixture was
2 4
extracted with DCM. The organic phases were combined and dried over anhydrous Na SO . After
removal of volatiles, a residue was obtained that was then subjected to silica-gel column
chromatographic purification to afford this intermediate 13a (196 mg, 63%).
To a stirred solution of 13a (178 mg, 0.40 mmol) in DMF (12 mL) at ambient temperature was
added 16a (155 mg, 0.46 mmol) and potassium carbonate (276 mg, 2.0 mmol) and potassium iodide.
After one night, the reaction mixture was filtrated and washed with ethyl acetate (140 mL). The
2 4
filtrate was washed with saturated brine and dried over anhydrous Na SO and the organic phase was
concentrated under vacuum to afford the yellow solid. Further purification was done by column
1
chromatography (152 mg, 54%). H NMR (400 MHz, CDCl
3
) δ 7.67 – 6.95 (m, 18H), 4.73 (s, 2H),
1
3
4
.41 (s, 2H), 4.29 (d, J = 5.7 Hz, 4H), 3.76 (s, 3H), 3.07 (s, 3H), 2.76 (s, 3H). C NMR (101 MHz,
DMSO-d
6
) δ 169.6, 139.3, 137.8, 137.6, 136.3, 136.2, 135.7, 133.3, 129.3, 128.8, 128.5, 128.3,
):
Analysis Calcd for N, 6.13; C, 56.04; S, 14.03; H, 5.14. Found: N, 5.969; C, 55.95; S, 14.54; H,
35 3 8 3
128.2, 128.1, 127.4, 127.3, 127.2, 52.8, 52.0, 51.9, 51.1, 50.4, 38.9, 38.2. Anal. (C32H N O S
4
.736.
6.1.4. [(4-{[{4-[(Benzyl-methanesulfonyl-amino)-methyl]-phenyl}-(4-methoxy-benzenesulfonyl)
-amino]-methyl}-phenyl)-methanesulfonyl-amino]-acetic acid methyl ester (P6)

The reaction mixture of phenol (3 g, 32 mmol) and KOH (2.69 g, 48 mmol) in methanol (40
mL) was stirred at 0°C under nitrogen for 15 min, then dimethylsulfate (6.06 g, 48 mmol) was added
dropwise in the reaction and the mixture was gradually heated to 60°C. The samples were withdrawn
at different time intervals and analyzed using TLC until the reaction was completed. Then it was
cooled to room temperature, poured into water, and extracted into ethyl acetate. The organic layer
2 4
was washed with water and 10% NaOH and dried over anhydrous Na SO . And the organic phase
was concentrated under vacuum to afford the colorless liquid as product. Further purification was
done by column chromatography affording 1.94 g (56%) of 11a as a colorless oil.
11a（1.84 g, 17 mmol）was dissolved in DCM (50 mL). Then chlorosulfonic acid (2.97 g, 25.5
mmol) in DCM (20 mL) was added over 60 min at -5°C. The mixture was allowed to warm to room
temperature with stirring additional 60 min. The mixture was poured into ice water and the organic
phase was separated, washed with Na
2 3 3
CO , NaHCO , water and saturated brine. It was finally dried
over anhydrous Na SO , filtered and evaporated, affording in 12a (2.11 g, 60%). According to the
2
4
same procedure described for 13a, 10a (203 mg, 0.7 mmol) was treated with 12a (157 mg, 0.76
mmol) to afford 228 mg (71%) of 13b as a white solid. According to the same procedure described
for P6, 13b (184 mg, 0.40 mmol) was treated with 16a (155 mg, 0.46 mmol) to afford 173 mg (61%)
1
of 7 as a white solid. H NMR (400 MHz, DMSO-d
6
) δ 7.49 (d, J = 8.8 Hz, 2H), 7.36 – 7.05 (m,
1
3
1
5
1
3H), 7.01 (d, J = 8.4 Hz, 2H), 4.73 (s, 2H), 4.45 (s, 2H), 4.23 (d, J = 14.8 Hz, 4H), 3.85 (s, 3H),
1
3
.58 (s, 3H), 3.03 (s, 3H), 2.88 (s, 3H). C NMR (101 MHz, DMSO-d
36.3, 136.0, 135.8, 129.6, 129.2, 128.8, 128.6, 128.3, 128.3, 128.1, 127.5, 127.2, 114.4, 55.8, 52.7,
2.0, 51.9, 51.1, 50.4, 38.9, 38.3. Anal. (C33 ): Analysis Calcd for N, 5.87; C, 55.37; S,
6
) δ 169.7, 162.8, 139.3, 138.1,
37 3 9 3
H N O S
3.44; H, 5.21. Found: N, 5.865; C, 55.08; S, 13.33; H, 4.829.
6
.1.5. [(4-{[{4-[(Benzyl-methanesulfonyl-amino)-methyl]-phenyl}-(4-ethoxy-benzenesulfonyl)-
amino]-methyl}-phenyl)-methanesulfonyl-amino]-acetic acid methyl ester (P7)
The phenol (1.88 g, 20 mmol) was dissolved in a mixture of DMF (50 mL) and potassium
carbonate (4.14 g，30 mmol), Then the bromoethane (2.3 mL, 30 mmol) was added and the mixture
was stirred for about 5 hours with heating and reflux at 70°C. The solids were removed by filtration
and washed with ethyl acetate (140 mL). The filtrate was washed with a saturated brine solution and
2 4
dried over anhydrous Na SO , and the organic phase was concentrated under vacuum to afford 1.72
g (70 %) of 11b as a colorless oil. According to the same procedure described for 12a, 11b (1.47 g,

12 mmol) was treated with chlorosulfonic acid (2.10 g, 18 mmol) to afford 1.41 g (53%) of 12b as a
colorless oil. According to the same procedure described for 13a, 10a (203 mg, 0.7 mmol) was
treated with 12b (168 mg, 0.76 mmol) to afford 236 mg (71%) of 13c as a red oil. According to the
same procedure described for P6, 13c (190 mg, 0.40 mmol) was treated with 16a (155 mg, 0.46
1
mmol) to afford 170 mg (58%) of P7 as a white solid. H NMR (400 MHz, CDCl
3
) δ 7.54 (d, J = 8.8
Hz, 2H), 7.40 – 7.29 (m, 7H), 7.26 – 7.13 (m, 4H), 7.01 (d, J = 8.4 Hz, 2H), 6.94 (d, J = 8.8 Hz, 2H),
4
3
1
5
5
.71 (s, 2H), 4.40 (s, 2H), 4.29 (d, J = 6.0 Hz, 4H), 4.12 (q, J = 6.8Hz, 2H), 3.76 (s, 3H), 3.07 (s,
1
3
H), 2.75 (s, 3H), 1.48 (t, J = 6.8 Hz, 3H). C NMR (101 MHz, DMSO-d
38.1, 136.3, 136.0, 135.8, 129.6, 128.9, 128.8, 128.5, 128.3, 128.2, 128.1, 127.4, 127.2, 114.8, 63.8,
2.7, 52.0, 51.9, 51.0, 50.3, 38.9, 38.3, 14.5. Anal. (C34 ): Analysis Calcd for N, 5.76; C,
6
) δ 169.6, 162.1, 139.2,
39 3 9 3
H N O S
5.95; S, 13.18; H, 5.39. Found: N, 5.662; C, 55.93; S, 13.70; H, 4.81.
6.1.6. [(4-{[{4-[(Benzyl-methanesulfonyl-amino)-methyl]-phenyl}-(4-propoxy-benzenesulfonyl)
-amino]-methyl}-phenyl)-methanesulfonyl-amino]-acetic acid methyl ester (P8)
According to the same procedure described for 11b, phenol (1.88 g, 20 mmol) was treated with
1
-bromopropane (2.7 mL, 30 mmol) to afford 1.95 g (72%) of 11c as a colorless oil. According to
the same procedure described for 12b, 11c (1.63 g, 12 mmol) was treated with chlorosulfonic acid
2.10 g, 18 mmol) to afford 1.42 g (50%) of 12c as a colorless oil. According to the same procedure
(
described for 13b, 10a (203 mg, 0.7 mmol ) was treated with 12b (178 mg，0.76 mmol) to afford 195
mg (60%) of 13d. According to the same procedure described for 6, 13d (195 mg, 0.40 mmol) was
1
treated with 16a (155 mg, 0.46 mmol) to afford 157 mg (53%) of P8 as a white solid. H NMR (400
6
MHz, DMSO-d ) δ 7.48 (d, J = 8.8 Hz, 2H), 7.35 – 6.99 (m, 15H), 4.74 (s, 2H), 4.46 (s, 2H), 4.24 (d,
J = 14.4 Hz, 4H), 4.03 (t, J = 6.4 Hz, 2H), 3.59 (s, 3H), 3.04 (s, 3H), 2.89 (s, 3H), 1.82 – 1.70 (m,
1
3
2
1
5
H), 1.00 (t, J = 7.6 Hz, 3H). C NMR (101 MHz, DMSO-d
36.0, 135.8, 129.6, 128.9, 128.7, 128.5, 128.3, 128.2, 128.1, 127.4, 127.2, 114.8, 69.6, 52.6, 52.0,
1.9, 51.0, 50.3, 38.9, 38.3, 21.9, 10.3. Anal. (C35 ): Analysis Calcd for N, 5.65; C, 56.51;
6
) δ 169.6, 162.2, 139.2, 138.1, 136.3,
41 3 9 3
H N O S
S, 12.93; H, 5.56. Found: N, 5.807; C, 56.60; S, 13.82; H, 5.466.
.1.7. [(4-{[{4-[(Benzyl-methanesulfonyl-amino)-methyl]-phenyl}-(4-butoxy-benzenesulfonyl)-
6
amino]-methyl}-phenyl)-methanesulfonyl-amino]-acetic acid methyl ester (P9)
According to the same procedure described for 11b, phenol (1.88 g, 20 mmol) was treated with
1
-bromobutane (3.2 mL, 30 mmol) afford 2.17 g (72%) of 11d as a colorless oil. According to the

same procedure described for 12a, 11d (1.80 g, 12 mmol) was treated with chlorosulfonic acid (2.10
g, 8 mmol) to afford 1.53 g (54%) of 12d as a colorless oil. According to the same procedure
described for 13a, 10a (203 mg, 0.7 mmol) was treated with 12d (178 mg, 0.76 mmol) to afford 204
mg (58%) of 13e. According to the same procedure described for P6, 13e ( 201 mg, 0.40 mmol) was
1
treated with 16a (155 mg, 0.46 mmol) to afford 167 mg (55%) of P9 as a white solid. H NMR (400
6
MHz, DMSO-d ) δ 7.48 (d, J = 7.6 Hz, 2H), 7.40 – 6.95 (m, 15H), 4.74 (s, 2H), 4.46 (s, 2H), 4.24 (d,
J = 14.0Hz, 4H), 4.07 (s, 2H), 3.59 (s, 3H), 3.04 (s, 3H), 2.89 (s, 3H), 1.73 (s, 2H), 1.45 (d, J =
1
3
6
1
5
.8Hz, 2H), 0.95 (s, 3H). C NMR (101 MHz, DMSO-d
35.8, 129.5, 128.9, 128.7, 128.5, 128.3, 128.2, 128.1, 127.4, 127.2, 114.8, 67.8, 52.6, 52.0, 51.9,
1.0, 50.3, 38.9, 38.3, 30.5, 18.7, 13.7. Anal. (C36 ): Analysis Calcd for N, 5.54; C, 57.05;
6
) δ 169.6, 162.2, 139.2, 138.1, 136.3, 136.0,
43 3 9 3
H N O S
S, 12.69; H, 5.72. Found: N, 5.548; C, 56.84; S, 13.03; H, 5.609.
.1.8. ({4-[({4-[(Benzyl-methanesulfonyl-amino)-methyl]-phenyl}-phenylmethanesulfonyl-amin
6
o)-methyl]-phenyl}-methanesulfonyl-amino)-acetic acid methyl ester (P10)
According to the same procedure described for 13a, 10a (203 mg, 0.7 mmol) was treated with
benzylsulfonyl chloride (145 mg, 0.76 mmol) to afford 197 mg (63%) of 13f. According to the same
procedure described for P6, 13f (178 mg, 0.40 mmol) was treated with 16a (155 mg, 0.46 mmol) to
1
afford 141 mg (50%) of P10 as a white solid. H NMR (400 MHz, DMSO-d
6
) δ 7.44 – 7.31 (m, 7H),
7
3
1
5
.25 – 7.11 (m, 11H), 4.80 (s, 2H), 4.56 (s, 2H), 4.46 (s, 2H), 4.26 (d, J = 9.6 Hz, 4H), 3.60 (s, 3H),
1
3
.04 (s, 3H), 2.91 (s, 3H). C NMR (101 MHz, DMSO-d
35.7, 131.0, 129.1, 128.8, 128.5, 128.4, 128.4, 128.3, 128.0, 127.4, 127.2, 55.9, 53.3, 52.0, 51.9,
1.0, 50.3, 38.8, 38.4. Anal. (C33 ): Analysis Calcd for N, 6.00; C, 56.63; S, 13.74; H, 5.33.
6
) δ 169.6, 139.3, 138.3, 136.3, 136.1,
37 3 8 3
H N O S
Found: N, 5.879; C, 56.59; S, 14.52; H, 4.919.
.1.9. [Methanesulfonyl-(4-{[(4-{[methanesulfonyl-(4-methyl-benzyl)-amino]-methyl}-phenyl)-
6
phenylmethanesulfonyl-amino]-methyl}-phenyl)-amino]-acetic acid methyl ester (P11)
According to the same procedure described for 9a, 8 (500 mg, 2.17mmol) was treated with
1
-bromomethyl-4-methyl-benzene (352 μL, 2.61 mmol) to afford 531 mg (73%) of 9b as a yellow
solid. According to the same procedure described for 10a, 9b (481 mg, 1.5 mmol) was treated with
NiCl ·6H O (618 mg, 2.6 mmol), NaBH (198 mg, 5.2 mmol) to afford 409 mg (90%) of 10b.
2
2
4
According to the same procedure described for 13a, 10b (213 mg, 0.7 mmol ) was treated with
benzylsulfonyl chloride (145 mg, 0.76 mmol) to afford 187 mg (58%) of 13g. According to the same

procedure described for P6, 13b (183 mg, 0.40 mmol) was treated with 16a (155 mg, 0.46 mmol) to
1
afford 146 mg (51%) of P11 as a white solid. H NMR (400 MHz, DMSO-d
6
) δ 7.48 – 7.29 (m, 7H),
7
2
1
5
5
.28 – 6.98 (m, 10H), 4.80 (s, 2H), 4.56 (s, 2H), 4.46 (s, 2H), 4.21 (s, 4H), 3.60 (s, 3H), 3.04 (s, 3H),
1
3
.88 (s, 3H), 2.23 (s, 3H). C NMR (101 MHz, DMSO-d
35.7, 133.2, 131.0, 129.1, 128.9, 128.8, 128.5, 128.4, 128.4, 128.0, 127.2, 55.9, 53.3, 52.0, 51.9,
0.4, 49.9, 38.8, 38.6, 20.7. Anal. (C34 ): Analysis Calcd for N, 5.89; C, 57.20; S, 13.47; H,
6
) δ 169.6, 139.3, 138.4, 136.7, 136.1,
39 3 8 3
H N O S
.51. Found: N, 6.225; C, 57.13; S, 13.31; H, 5.621.
6.1.10. [(4-{[(4-{[(3-Chloro-benzyl)-methanesulfonyl-amino]-methyl}-phenyl)-phenylmethanes
ulfonyl-amino]-methyl}-phenyl)-methanesulfonyl-amino]-acetic acid methyl ester (P12)
According to the same procedure described for 14a, 4-methyl-aniline (4.29 g, 40 mmol) was
treated with ethanesulfonyl chloride (5.66 g, 44 mmol) to afford 6.4 g (80%) of 14b as a colorless
solid. According to the same procedure described for 15a, 14b (4.58 g, 23 mmol) was treated with
methyl bromoacetate (3 mL, 32mmol) to afford 4.926 g (77%) of 15b as a white solid. According to
the same procedure described for 16a, 15b (4.07 g, 15 mmol) was treated with NBS (2.94 g, 16.5
mmol) and AIBN to afford 3.55 g (70%) of 16b as a white solid. According to the same procedure
described for 9a, 8 (500 mg, 2.17 mmol) was treated with 3-chlorobenzyl bromide (536 mg, 2.61
mmol) to afford 556 mg (72 %) of 9c. According to the same procedure described for 10a, 9c (532
2 2 4
mg, 1.5 mmol) was treated with NiCl ·6H O (618 mg, 2.6 mmol), NaBH (197 mg, 5.2 mmol) to
afford 430 mg (88%) of 10c. According to the same procedure described for 13a, 10c (227 mg, 0.7
mmol) was treated with benzylsulfonyl chloride (145 mg, 0.76 mmol) to afford 189 mg (56%) of
13h. According to the same procedure described for P6, 13h (192 mg, 0.40 mmol) was treated with
1
1
6b(155 mg, 0.46 mmol) to afford 156 mg (52%) of P12 as a white solid. H NMR (400 MHz,
6
DMSO-d ) δ 7.56 – 6.97 (m, 17H), 4.78 (s, 2H), 4.54 (s, 2H), 4.47 (s, 2H), 4.29 (d, J = 10.4 Hz, 4H),
1
3
3
.58 (s, 3H), 3.17 (q, J = 7.3 Hz, 2H), 2.95 (s, 3H), 1.17 (t, J = 7.6 Hz, 3H). C NMR (101 MHz,
3
CDCl ) δ 170.4, 139.8, 138.9, 137.6, 136.6, 135.1, 134.7, 131.0, 130.2, 129.5, 129.3, 129.2, 129.1,
1
28.8, 128.7, 128.6, 128.4, 128.2, 126.9, 57.9, 54.9, 53.0, 52.6, 50.4, 50.3, 47.4, 40.1, 8.0. Anal.
): Analysis Calcd for N, 5.62; C, 54.57; S, 12.85; H, 5.12. Found: N, 5.64; C, 54.43;
S, 12.98; H, 4.604.
34 3 8 3
(C H38ClN O S
6.1.11. {[4-({[4-(Benzyl-methanesulfonyl-amino)-phenyl]-phenylmethanesulfonyl-amino}-meth
yl)-phenyl]-methanesulfonyl-amino}-acetic acid methyl ester (P13)

According to the same procedure described for 8, p-nitroaniline (3.59 g, 26 mmol) was treated
with methanesulfonyl chloride (2.24 mL, 29 mmol) to afford 4.68 g (83%) of 17 a yellow solid.
According to the same procedure described for 9a, 17 (469 mg, 2.17 mmol) was treated with benzyl
bromide (310 μL, 2.61 mmol) to afford 500 mg (75.3%) of 18a as a white solid. According to the
same procedure described for 10a, 18a (460 mg, 1.5 mmol) was treated with NiCl
2 2
·6H O (618 mg,
2
.6 mmol), NaBH (197 mg, 5.2 mmol) to afford 375 mg (90.5%) of 19b. According to the same
4
procedure described for 13a, 19b (194 mg, 0.7 mmol ) was treated with benzylsulfonyl chloride (145
mg, 0.76 mmol) to afford 182 mg (60%) of 20a as a white solid. According to the same procedure
described for P6, 20a (172 mg, 0.40 mmol) was treated with 16a (155 mg, 0.46 mmol) to afford 154
1
mg (56%) of P13 as a white solid. H NMR (400 MHz, CDCl
3
) δ 7.41 – 7.06 (m, 18H), 4.82 (s, 2H),
1
3
4
.47 (s, 2H), 4.40 (s, 2H), 4.31 (s, 2H), 3.82 – 3.71 (m, 3H), 3.07 (s, 3H), 2.94 (s, 3H). C NMR
101 MHz, DMSO-d ) δ 169.7, 139.3, 138.2, 138.0, 136.6, 136.0, 131.0, 129.0, 128.6, 128.5, 128.3,
28.3, 127.8, 127.4, 127.1, 56.2, 53.5, 53.2, 52.1, 51.9, 38.8, 37.4. Anal. (C32 ): Analysis
(
6
1
35 3 8 3
H N O S
Calcd for N, 6.13; C, 56.04; S, 14.03; H, 5.14. Found: N, 6.29; C, 56.02; S, 14.03; H, 4.869.
.1.12. ({4-[({4-[(3-Chloro-benzyl)-methanesulfonyl-amino]-phenyl}-phenylmethanesulfonyl-a
6
mino)-methyl]-phenyl}-methanesulfonyl-amino)-acetic acid methyl ester (P14)
According to the same procedure described for 18a, 17 (469 mg, 2.17 mmol) was treated with
3
-chlorobenzyl bromide (536 mg, 2.61 mmol) to afford 546 mg (74%) of 18b as a yellow solid.
According to the same procedure described for 10a, 18b (511 mg, 1.5 mmol) was treated with
NiCl ·6H O (618 mg, 2.6 mmol), NaBH (197 mg, 5.2 mmol) to afford 408 mg (88%) of 19b.
2
2
4
According to the same procedure described for 13a, 19b (218 mg, 0.7 mmol) was treated with
benzylsulfonyl chloride (145 mg, 0.76 mmol) to afford 184 mg (57%) of 20b as a white solid.
According to the same procedure described for P6, 20b (186 mg, 0.40 mmol) was treated with 16a
1
(
155 mg, 0.46 mmol) to afford 147 mg (51%) of P14 as a white solid. H NMR (400 MHz,
6
DMSO-d ) δ 7.45 – 7.11 (m, 17H), 4.81 (d, J = 10.8 Hz, 4H), 4.61 (s, 2H), 4.46 (s, 2H), 3.62 (s, 3H),
1
3
3
1
5
.13 – 2.99 (m, 6H). C NMR (101 MHz, DMSO-d
33.0, 131.0, 130.3, 129.0, 128.5, 128.5, 128.4, 128.3, 128.3, 127.5, 127.4, 127.1, 126.5, 56.2, 53.2,
2.9, 52.1, 51.9, 38.8, 37.4. Anal. (C32 ): Analysis Calcd for N, 5.83; C, 53.36; S, 13.36;
6
) δ 169.7, 139.4, 139.3, 138.4, 137.8, 136.1,
3 8 3
H34ClN O S
H, 4.76. Found: N, 5.724; C, 53.08; S, 13.62; H, 4.409.
6.1.13. {Ethanesulfonyl-[4-({[4-(4-ethoxy-benzenesulfonylamino)-phenyl]-phenylmethanesulfo
nyl-amino}-methyl)-phenyl]-amino}-acetic acid methyl ester (P15)

According to the same procedure described for 13a, p-nitroaniline (2.76 g, 20 mmol) was
treated with benzylsulfonyl chloride (4.20 g, 22 mmol) to afford 2.65g (45%) of 21a. According to
the same procedure described for P6, 21a (292 mg, 1 mmol) was treated with 16b (385 mg, 1.1
mmol) to afford 309 mg (55%) of 22a. According to the same procedure described for 10a, 22a (281
2 2 4
mg, 0.5 mmol) was treated with NiCl ·6H O (214 mg, 0.9 mmol), NaBH (68 mg, 1.8 mmol) to
afford 253 mg (95%) of 23a. According to the same procedure described for 13a, 23a (213 mg, 0.4
1
mmol) was treated with 12b (97 mg, 0.44 mmol) to afford 158 mg (56%) of P15 as a white solid. H
6
NMR (400 MHz, DMSO-d ) δ 10.27 (s, 1H), 7.65 (d, J = 8.4 Hz, 2H), 7.42 – 7.28 (m, 7H), 7.16 (d,
J = 8.0 Hz, 2H), 7.10 (d, J = 8.4 Hz, 2H), 7.03 (d, J = 8.4Hz, 2H), 6.95 (d, J = 8.4 Hz, 2H), 4.70 (s,
2
1
1
5
H), 4.52 (s, 2H), 4.46 (s, 2H), 4.06 (m, 2H), 3.59 (s, 3H), 3.16 (m, 2H), 1.30 (t, J = 6.8 Hz, 3H),
1
3
.15 (t, J = 7.2 Hz, 3H). C NMR (101 MHz, CDCl
30.9, 130.3, 129.7, 129.5, 129.5, 129.1, 129.0, 128.6, 128.1, 121.2, 114.8, 64.2, 57.7, 55.1, 53.0,
2.6, 47.4, 14.7, 8.0. Anal. (C33 ): Analysis Calcd for N, 5.87; C, 55.37; S, 13.44; H, 5.21.
3
) δ 170.4, 162.9, 139.7, 136.5, 136.4, 135.4,
37 3 9 3
H N O S
Found: N, 5.681; C, 55.12; S, 13.91; H, 4.774.
.1.14. {[4-({[4-(Benzenesulfonylmethyl-amino)-phenyl]-phenylmethanesulfonyl-amino}-methy
6
l)-phenyl]-ethanesulfonyl-amino}-acetic acid methyl ester (P16)
According to the same procedure described for P15, 23b (236 mg, 0.4 mmol) was treated with
1
benzylsulfonyl chloride (84 mg, 0.44 mmol) to afford 149 mg (50%) of P16 as a white solid. H
NMR (400 MHz, DMSO-d
6
) δ 9.90 (s, 1H), 7.66 – 6.89 (m, 17H), 4.73 (s, 2H), 4.41 (d, J = 3.2Hz,
4
0
1
3
H), 4.07 (t, J = 6.4 Hz, 2H), 3.59 (s, 3H), 3.03 (s, 3H), 1.84 – 1.63 (m, 2H), 1.45 (m, 2H), 1.06 –
13
.83 (m, 3H). C NMR (101 MHz, DMSO-d
29.6, 129.3, 129.2, 129.0, 128.6, 128.3, 128.2, 127.2, 118.6, 114.8, 67.8, 57.3, 52.8, 52.0, 51.9, 38.8,
0.6, 18.7, 13.7. Anal. (C35 ): Analysis Calcd for N, 5.65; C, 56.51; S, 12.93; H, 5.56.
6
) δ 169.6, 162.2, 139.3, 137.8, 135.9, 133.8, 130.9,
41 3 9 3
H N O S
Found: N, 5.71; C, 55.88; S, 13.68; H, 4.683.
6.2. PTP1B and related PTPs biological assay
34, 39
PTP1B inhibitory activities were measured as previously described with minor revision.
Briefly, PTP1B hydrolyzes pNPP to pNP that can be detected at 405 nm. Test compounds were
predispensed in 96-well microplates as 1.0 µL aliquots per well in 100% DMSO. The PTP1B
enzymatic assay was carried out in a total volume of 100 µL per well in assay plates with 15 nM
recombinant PTP1B protein, 2 mM p-nitrophenylphosphonic acid (pNPP), 1 mM dithiothreitol and 1

o
mM EDTA (pH 6.5). After 30 min incubation at 37 C, the reaction was terminated by addition of 2.5
M NaOH. The amount of hydrolysis product, pNP, was monitored by detection of the absorbance at
405 nm. To determine cross-reactivity of test compounds, the same protocol was followed for
inhibition assay with TCPTP. To study the inhibition on the other PTPs family members, SHP1,
SHP2 and LAR assays were performed according to procedures described previously.
6
.3. Effect of PTP1B inhibitors on the phosphorylation level of IR in transfected CHO cells and
T3-L1 cells
3
CHO cells were cultured in the presence of F12 supplemented with 10% FBS and seeded 24 h
5
before transfection in 6 cm dish (6 ×1 0 cells per dish). 2μg of the human IR plasmid was introduced
into cells by using Fu GENE 6 transfection reagent (Roche) according to the manufacturer’s protocol.
Cells were transfected for 8 h, and harvested with 0.05% trypsin and 0.02% EDTA prior to reseeding
o
onto a 6-well plate. After 24 h with 5% CO
2
at 37 C, CHO cells serum free starved for 2 h were
incubated with compounds for 4 h, then 10 nM insulin was added stimulation for 10 min before
harvested.
For total protein extraction, CHO cells were lysed in the ice-cold buffer A (1% Triton X-100,
1
7
00 mM sodium pyrophosphate, 2 mM phenylmethylsulfonyl fluoride (PMSF), 50 mM HEPES, pH
.4) and centrifuged at 15, 000 ×g for 20 min at 4°C. Supernatants were collected and stored at -80°C.
For subcellular fractionation, cells were lysed in buffer B (0.25 M sucrose, 2 mM EDTA, 1 mM
phenylmethylsulfony fluoride (PMSF) and 10 mM Tris-HCl, pH 7.4). The lysates were centrifuged
at 750 ×g for 15 min, and the supernatants were centrifuged at 12, 000 ×g for 20 min to isolate the
crude plasma membrane fraction as the pellets. Equal amount of protein from each sample were
denatured and subjected to SDS-PAGE and blotted on PVDF membrane, which was incubated for 2
h at room temperature with blocking buffer (5% non-fat milk, 0.1% Tween 20, in TBS, pH 7.6) and
then probed with primary antibodies (PY-20 and β-actin) overnight at 4°C. After incubation with the
appropriate secondary antibodies, the immunoreactive band was detected by an ECL Western
blotting detection system (GE Healthcare).
To determine the phosphorylation level of IRβ in 3T3-L1 cells, the total protein extraction of
P7-treated cells were resolved by SDS-PAGE and immunoblotted with anti-pIRβ or anti-IRβ
antibody.

6
.4. Glucose uptake assay
-NBDG is a fluorescent glucose analogue. Glucose uptake into L6 myotubes or human skeletal
2
4
0, 41
muscle cells (HSkMC) was measured using 2-NBDG as previously described.
Briefly, L6
myoblasts were grown in 96-well fluorescent plates and differentiated as described above. HSkMC
were also grown in 96-well fluorescent plates. Differentiated L6 myotubes or HSkMC were washed
o
once with warm PBS, incubated in serum-free DMEM for 3 h at 37 C and then stimulated with
o
either 10 nM insulin for 10 min at 37 C in Kreb's ringer phosphate buffer (128 mM NaCl, 4.7 mM
2 4 4
KCl, 1.25 mM CaCl , 1.25 mM MgSO , 10 mM NaPO , pH 7.4). Glucose uptake was initiated by
the addition of 80 µM 2-NBDG to each well. After 30 min, the supernatant was removed. Plates
were then rinsed with PBS and the fluorescence of the samples was monitored at an excitation
wavelength of 485 nm and an emission wave length of 535 nm. To exclude false-positive, cells
treated with drugs in the absence of 2-NBDG were measured and taken as the background. The
relative fluorescence intensities minus the background were used for subsequent data analysis.
6
.5. Molecular Docking
All the molecular docking into the pocket of PTP1B in the open conformation have been
performed using the Surflex-Dock docking module within the software Sybyl X 1.0 with the default
settings. The X-ray crystal structure of PTP1B (PDB code 1Q6T) was retrieved from the RCSB
Protein Data Bank (http://www.rcsb.org).
Acknowledgment
This work was supported by a grant from the National Natural Science Foundation of China
(
81202389 and 81302853)
References and notes
1
2
3
4
5
. Taylor, S. D.; Hill, B. Expert Opin. Investig. Drugs 2004, 13, 199.
. Taniguchi, C. M.; Emanuelli, B.; Kahn, C. R. Nat. Rev. Mol. Cell. Biol. 2006, 7, 85.
. Moller. Nature 2001, 414, 821.
. Wälchli, S.; Curchod, M-L.; Gobert, R. P., et al. J. Biol. Chem. 2000, 275, 9792.
. Goldstein, B. J; Bittner-Kowalczyk, A.; White, M. F.; Harbeck, M. J. Biol. Chem. 2000, 275,

4
283.
6
7
8
. Zabolotny, J. M.; Bence-Hanulec, K. K.; Stricker-Krongrad, A.; Haj, F.; Wang, Y. P.; Minokoshi,
Y.; Kim, Y.-B., et al. Dev. Cell 2002, 2, 489.
. Cheng, A.; Uetani, N.; Simoncic, P. D.; Chaubey, V. P.; Lee-Loy, A.; McGlade, C. J.; Kennedy,
B. P.; Tremblay, M. L. Dev. Cell 2002, 2, 497.
. Lund, I. K.; Hansen, J. A.; Andersen, H. S.; Moller, N. P.; Billestrup, N. J. Mol. Endocrinol.
2005, 34, 339.
9. Zhang, S.; Zhang, Z. Y. Drug Discovery Today 2007, 12, 373.
1
0. Elchebly, M.; Payette, A.; Michaliszyn, E.; Cromlish, W.; Collins, S.; Loy, A. L.; Normandin,
D.; Kennedy, B. P., et al. Science 1999, 283, 1544.
11. Klaman, L. D.; Boss, O. Peroni, O. D.; Kim, J. K.; Martino, J. L.; Zabolotny, J. M.; Moghal, N.;
Lubkin, M.; Kim, Y-B.; Sharpe, A. H., et al. Mol. Cell. Biol. 2000, 20, 5479.
12. You-Ten, K. E.; Muise, E. S.; Itié, A,; Michaliszyn, E. Wagner, J.; Jothy, S.; Lapp, W. S.;
Tremblay, M. L. J. Exp. Med. 1997, 186, 683.
1
1
1
1
3. Johnson, T. O.; Ermolieff, J.; Jirousek, M. R. Nat. Rev. Drug Disc. 2002, 1, 696.
4. He, R. J.; Zeng, L-F.; He, Y. T.; Zhang, S.; Zhang, Z-Y. FEBS J. 2013, 280, 731.
5. Tamrakar, A. K.; K Maurya, C. K.; Rai , A. K. Expert Opin. Ther. Pat. 2014, 24, 1.
6. Erbe, D. V.; Wang, S.; Zhang, Y. L.; Harding, K.; Kung, L.;Tam, M.; Stolz, L.; Xing, Y.; Furey,
S.; Qadri, A.; Klaman, L. D.; Tobin, J. F. Mol. Pharmacol. 2005, 67, 69.
1
7. Basu, S.; Prasad, U. V.; Barawkar, D. A.; De, S.; Palle, V. P.; Menon, S., Patel, M.; Thorat, S.;
Singh, U. P.; Das Sarma, K.; Waman, Y.; Niranjan, S.; Pathade, V.; Gaur, A.; Reddy, S.; Ansari,
S. Bioorg. Med. Chem. Lett. 2012, 22, 2843.
18. Lantz, K. A.; Hart, S. G. E.; Planey, S. L.; Roitman, M. F.; Ruiz-White, I. A.; Wolfe, H. R.;
McLane, M. P. Obesity 2010, 18, 1516.
1
9. Barr, A. J. Future Med. Chem. 2010, 2, 1563.
20. Iversen, L. F.; Moller, K. B.; Pedersen, A. K.; Peters, G. H.; Petersen, A. S.; Andersen, H. S.;

Branner, S.; Mortensen, S. B.; Moller, N. P. J. Biol. Chem. 2002, 277, 19982.
2
1. Shen, K.; Keng, Y.-F.; Wu, L.; Guo, X.-L.; Lawrence, D. S.; Zhang, Z.-Y. J. Biol. Chem. 2001,
276, 47311.
2
2
2. Combs, A. P. J. Med. Chem. 2010, 53, 2333.
3. Ala, P. J.; Gonneville, L.; Hillman, M.; Becker-Pasha, M.; Yue, E. W.; Douty, B.; Wayland, B.;
Polam, P.; Crawley, M. L.; McLaughlin, E.; Sparks, R. B., Glass, B.; Takvorian, A.; Combs, A.
P.; Burn, T. C.; Hollis, G. F.; Wynn, R. J. Biol. Chem. 2006, 281, 38013.
2
2
2
2
4. Du, Y. L.; Ling, H.; Zhang, M.; Shen, J. K.; Li, Q. Y. Bioorg. Med. Chem. 2015, 23, 4891.
5. Rui Cao, P. M.; Stephen J. J. Am. Chem. Soc. 2010, 132, 17366.
6. Ali, I. A. I.; El Ashry, E. S. H.; Schmidt, R. R. Tetrahedron 2004, 60, 4773.
7. Koshio, H.; Hirayama, F.; Ishihara, T.; Taniuchi, Y.; Sato, K.; Sakai-Moritani, Y.; Kaku, S.;
Kawasaki, T.; Matsumoto, Y.; Sakamoto, S.; Tsukamoto, S. Bioorg. Med. Chem. 2004, 12,
2
179.
28. Lis, R.; Marisca, A. J. J. Org. Chem. 1987, 52, 4377.
2
9. Takeuchi, Y.; Oda, T.; Chang, M. R.; Okamoto, Y.; Ono, J., et al. Chem. Pharm. Bull. 1997, 45,
2
406.
3
0. Rassadin, V. A.; Grosheva, D. S.; Arefeva, I. A.; Tomashevskiy, A. A.; Sokolov, V. V.;
Meijere, A. D. Eur. J. Org. Chem. 2012, 9, 5028.
3
3
3
1. Singh, H.; Balamurugan, A.; Jayakannan, M. ACS Appl. Mat. Interfaces 2013, 5, 5578.
2. Hanessian, S.; Auzzas, L. Acc. Chem. Res. 2008, 41, 1241.
3. Lakshminarayana, N.; Prasad, Y. R.; Gharat, L.; Thomas, A.; Narayanan, S.; Raghuram, A.;
Srinivasan, C. V.; Gopalan, B. Eur. J. Med. Chem. 2010, 45, 3709.
3
4. Otake, K.; Azukizawa, S.; Fukui, M.; Kunishiro, K.; Kamemoto, H.; Kanda, M.; Miike, T.;
Kasai, M.; Shirahase, H. Bioorg. Med. Chem. 2012, 20, 1060.
35. Panzhinskiy, E.; Ren, J.; Nair, S. Curr. Med. Chem. 2013, 20, 2609.

3
3
6. Zinker, B. A.; Rondinone, C. M.; Trevillyan, J. M.; Gum, R. J.; Clampit, J. E.; Waring, J. F.;
Xie, N.; Wilcox, D.; Jacobson, P.; Frost, L.; Kroeger, P. E.; Reilly, R. M.; Koterski, S.;
Opgenorth, T. J.; Ulrich, R. G.; Crosby, S.; Butler, M., et al. Proc. Natl. Acad. Sci. U. S. A.
2
002, 99, 11357.
7. Fukuda, S.; Ohta, T., Sakata, S.; Morinaga, H.; Ito, M.; Nakagawa, Y.; Tanaka, M.; Matsushita,
M. Diabetes Obes. Metab. 2010, 12, 299.
3
3
8. Maeda, A.; Kai, K.; Ishii, M.; Ishii, T.; Akagawa, M. Mol. Nutr. Food Res. 2014, 58, 1177.
9. Lakshminarayana, N.; Prasad, Y. R.; Gharat, L.; Thomas, A.; Narayanan, S., Raghuram, A.;
Srinivasan, C. V.; Gopalan, B. Eur. J. Med. Chem. 2010, 45, 3709.
40. Qiu, J.; Maekawa, K.; Kitamura, Y.; Miyata, Y.; Tanaka, K.; Tanaka, T.; Soga, M.; Tsuda, T.;
Matsui, T. Biochem. Pharmacol. 2014, 87, 344.
41. Chen, L.; Li, Q. Y.; Shi, X. J.; Mao, S. L.; Du, Y. L. J. Agric. Food Chem. 2013, 61, 10714.

*Graphical Abstract:
OH
O
O
O
OH
O
CMS moiety
S
O
N
bioisosteric replacement
and combination
fragment
growing
N
S
O
O
N
O
O
O
S
S
O
O
N
R1
O
F
F
O
O
O
P
HO
OH
P7
fragment 3
IC50 = 222 nM (PTP1B)
IC50 = 1860 nM (TCPTP )
DFMP moiety