Three-Arm, Biotin-Tagged Carbazole–Dicyanovinyl–Chlorambucil Conjugate: Simultaneous Tumor Targeting, Sensing, and Photoresponsive Anticancer Drug Delivery

Article abstract of DOI:10.1002/asia.201601264

The design, synthesis, and in vitro biological studies of a biotin–carbazole–dicyanovinyl–chlorambucil conjugate (Bio-CBZ-DCV-CBL; 6) are reported. This conjugate (6) is a multifunctional single-molecule appliance composed of a thiol-sensor DCV functionality, a CBZ-derived phototrigger as well as fluorescent reporter, and CBL as the anticancer drug, and Bio as the cancer-targeting ligand. In conjugate 6, the DCV bond undergoes a thiol–ene click reaction at pH<7 with intracellular thiols, thereby shutting down internal charge transfer between the donor CBZ and acceptor DCV units, resulting in a change of the fluorescence color from green to blue, and thereby, sensing the tumor microenvironment. Subsequent photoirradiation results in release of the anticancer drug CBL in a controlled manner.

Full text of DOI:10.1002/asia.201601264

CHEMISTRY
AN ASIAN JOURNAL
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Accepted Article
Title: Three Arm, Biotin-tagged Carbazole-Dicyanovinyl-Chlorambucil Conjugate: Si-
multaneous Tumor Targetting, Sensing and Photoresponsive Anticancer Drug
Delivery
Authors: Pradeep Singh; Yarra Venkatesh; S Karthik; Y Rajesh; Mahitosh Mandal;
Avijit Jana
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Three Arm, Biotin-tagged Carbazole-Dicyanovinyl-Chlorambucil
Conjugate: Simultaneous Tumor Targetting, Sensing and
Photoresponsive Anticancer Drug Delivery
Yarra Venkatesh,[a] S. Karthik,[a] Y. Rajesh,[b] Mahitosh Mandal,[b] Avijit Jana,*[c, d] and N. D. Pradeep
Singh*[a]
Abstract: Here we report the design, synthesis and in vitro
quantification of GSH under physiological conditions are of
significant interest in clinical medicine.
biological studies of a Biotin-Carbazole-Dicyanovinyl-Chlorambucil
conjugate (Bio-CBZ-DCV-CBL). This conjugate (6) is
a
multifunctional single molecule appliance composed of thiol-sensor
Dicyanovinyl functionality, a Carbazole derived phototrigger and the
fluorescent reporter, chlorambucil (CBL) as the anticancer drug, and
biotin as the cancer-targeting ligand. In conjugate 6, the dicyanovinyl
bond undergoes thiol-ene click reaction at pH< 7 with intracellular
thiols thereby shuttingdown the internal charge transfer between
donor carbazole and acceptor dicyanovinyl unit results in change of
fluorescence color from green to blue and thereby sense the tumor
microenvironment, followed by photoirradiation results in release of
the anticancer drug CBL in controlled manner.
In this circumstances recently, several multifunctional disulfide-
linkage based bio-conjugates have been investigated either to
sense and quantify the intracellular thiols level or to exploit the
higher level of thiols in tumor site to trigger the release of
payloads from a redox responsive DDS.17
Recently, photoresponsive theranostic DDSs have achieved
enormous interest since they allow precise control over the drug
release, including location, timing and dosage through an active
ingredient “phototrigger”. A number of photoresponsive DDSs
have been developed, employing o-nitrobenzyl,18 coumarinyl19
and perylene20,21 derivatives as phototriggers for efficient drug or
gene delivery.
Tumor-targetability coupled with stimuli responsiveness of a
theranostic drug delivery systems (DDSs) have gained
tremendous attention in recent years.1,2 It offers early detection
and diagnosis of cancers along with improved therapeutic
efficacy by the means of enhanced spatiotemporal accumulation
of the therapeutic payload.3 Which further lowers the cytotoxic
effect of the therapeutic drug other than the tumor sites and also
favors overcoming the drug resistance.4, 5 These class of DDSs
are mostly composed of three ingredients (i) a stimuli responsive
prodrug (mostly sensitive to either light irradiation,6 intracellular
thiols,7-9 enzymes,10,11 or intracellular pH12,13 etc.) (ii) a tumor
targeting ligand and (iii) a monitoring tag which could allow us to
visualize, quantify and also track the spatial distribution,
localization, and depletion of both the DDS and the therapeutic
drug.
Biological thiols, including glutathione (GSH), cysteine (Cys),
and homocysteine (Hcy) plays crucial roles in maintaining the
appropriate redox status of biological systems. It has already
been established that an abnormal levels of cellular thiols are
associated with many diseases.14 GSH is the most abundant
cellular thiol, which is important for maintenance of cellular
defense against free radicals and reactive oxygen species
(ROS) and it also maintains exogenous antioxidants in their
reduced forms.15 Further, it is also reported that high level of
biological thiols (common in tumor tissues) offers resistance to
chemotherapy drugs.16 Therefore, selective detection and
Scheme 1. Schematic Representation of Multifunctional DDS: Tumor
Targetability by Biotin Functionalization and Intracellular GSH Sensing by the
means of Thiol-Ene Reaction with Dicyanovinyl Group Followed by
Photoresponsive Anticancer Drug Release from the Carbazole FPRPG.
Here, in this report, we developed an efficient new theranostic
DDS based on carbazole fluorescent Photoremovable protecting
group (FPRPG), which consecutively performs three different
roles. (i) Firstly it actively targets the cancerous cells, thereby
facilitate tumor targeted transportation of the designed DDS. (ii)
Secondly it can sense the intracellular thiols level of cancer cells
by the means of change in fluorescence color. And (iii) finally, it
can release the anticancer drug chlorambucil (CBL) on exposure
to UV light. The Bio-CBZ-DCV-CBL conjugate described here
composed of four components: (i) a biotin (Bio) unit as the
tumor-targeting ligand (ii) a carbazole (CBZ) moiety as the
phototrigger and fluorescent imaging agent (iii) a dicyanovinyl
(DCV) moiety to sense the intracellular biological thiols at pH< 7,
and (iv) light-triggered releasable anticancer drug chlorambucil
(CBL).
[a]
[b]
Yarra Venkatesh, S. Karthik and N. D. Pradeep Singh
Department of Chemistry, Indian Institute of Technology Kharagpur,
721302, West Bengal, E-mail: ndpradeep@chem.iitkgp.ernet.in
Y. Rajesh, Mahitosh Mandal
School of Medical Science and Technology, Indian Institute of
Technology Kharagpur, 721302, West Bengal,
[c, d] Avijit Jana,
Biomaterials
The design of the present theranostic DDS (Bio-CBZ-DCV-CBL)
is rationalize in such a way that initially it exhibits green emission
because of the efficient internal charge transfer (ICT) transition
from the carbazole donor unit to the dicyanovinyl acceptor unit
Group,
Division
of
Natural
Products
Chemistry, CSIR-Indian Institute of Chemical Technology,
Hyderabad, 500007, India
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which again restrict the photoinduced drug release process.
After internalization of the Bio-CBZ-DCV-CBL by the cancer
cells the dicyanovinyl bond will undergo thiol-ene click reaction
with intracellular thiols already abundant in higher concentration.
Therefore, the extended conjugation and the ICT transition
between the acceptor and the donor will be suppressed totally.
Which further leads to the radical change in the emission from
green to blue. Finally, photoirradiation of CBZ-DCV-CBL-ME
conjugate will release the anticancer drug chlorambucil in a
control manner as shown in Scheme 1.
thiols on the absorption and emission profile of CBZ-DCV-CBL
conjugate it was titrated against different concentration of GSH.
In case of absorption spectra, upon gradual addition of GSH (5.0
mM) to the solution of 5, the peak at 385 nm corresponds to ICT
transition gradually decreases whereas the peak at 316 nm
corresponds to the localized n–π* transition of the acetyl
carbazole remains almost same (Figure 1a). Similar
spectroscopic changes were also observed upon the addition
Cys and Hcy (see Figure S10 in SI). Which clearly indicates
that a chemical reaction has taken place between 5 and GSH
which restricted the extended conjugation between the
carbazole donor and the dicyanovinyl acceptor.
The Bio-CBZ-DCV-CBL conjugate was synthesized as shown in
the Scheme 2. First, 9-propargyl carbazole (1) was synthesized
from 9H-carbazole by reacting it with propargyl bromide. Then 2
was obtained by Vilsmeier–Haack reaction of 1 using dry
dimethylformamide (DMF) and phosphorus oxychloride (POCl3).
Later on, compound 3 was synthesized by the Knoevenagel
condensation of 2 with malononitrile in presence of catalytic
amount of piperidine and followed by Friedel-Crafts acylation of
compound 3 with bromoacetyl bromide in presence of catalytic
amount of AlCl3 afforded compound 4. Then CBZ–DCV-CBL
conjugate (5) was obtained by reacting compound 4 with
chlorambucil. Finally, Biotin-tagged CBZ–DCV-CBL conjugate
(6) was synthesized by click reaction between 5 and azido-biotin
(synthesized separately inset of Scheme 2). All the synthesized
Figure 1. UV-Vis absorption spectra (a) and emission spectra (b) of 5 (10 μM)
in DMSO/PBS buffer (1:10) during the course of titration with GSH (5.0 mM at
pH 5.5 (Excitation wavelength: 410 nm).
1
compounds were characterized by H, 13C NMR, IR and mass
spectral analysis (see Figure S1-9 in SI).
The excitation of the CBZ-DCV-CBL (5) at 410 nm produced a
dual emission with peaks at 475 and 533 nm respectively. We
presume that the appearance of dual emission attributable to the
localized π–π* (475 nm)) and ICT (533 nm) excited states
originates from the tilted molecular arrangement. Gradual
addition of GSH to 5 decreased the intensity of the peak at 533
nm. After the addition of 1.5 equivalent of GSH, the peak at 533
nm was completely quenched as shown in Figure 1b. Similar
spectroscopic changes were also observed upon the addition
Cys and Hcy which further supports the postulation of addition
reaction between GSH and 5 and produces an appreciable
visual color change from green to blue. However, such spectral
changes were not observed upon addition of nonthiol amino
acids see Figure 2 and Figure S11 in SI.
Scheme 2. Synthesis of Multifunctional DDS Bio-CBZ-DCV-CBL conjugate.
After successful synthesis of the Bio-CBZ-DCV-CBL conjugate
(6) its photophysical properties were investigated in details.
UV/Vis absorption and emission spectra of the conjugate 5 were
recorded in DMSO/PBS buffer (1:10 v/v) at pH 5.5 in 37 °C. In
the UV/vis spectrum, as seen in Figure 1a, the conjugate 5 (10
µM) shows two distinct absorption bands at 316 nm and 385 nm
respectively. The absorption band at 316 nm corresponded to a
localized n–π* transition of acetyl carbazole, whereas the band
at longer wavelength of 385 was attributed to intramolecular
charge transfer (ICT) transition from the carbazole donor moiety
to the dicyanovinyl acceptor. Now, to understand the role of
Figure 2. Relative fluorescence color changes of 5 (10 µM) upon addition of
1.5 equiv of GSH, Cys, Hcy and various amino acids at pH 5.5. Insets show
the photographs of respective solutions under fluorescent lamp (top) and
ambient light (bottom).
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Time-dependent fluorescent spectra of CBZ-DCV-CBL (10 μM)
were monitored in the presence of GSH (5 mM) in DMSO/PBS
buffer (1:10 v/v, pH 5.5). The formation of CBZ-DCV-CBL+GSH
was complete within 80 min with a rate constant of kobs = 4.5 ×
10−4 s−1 under the pseudo first-order reaction conditions (Figure
S12 in SI).
the photocleavage of CBZ-DCV-CBL-ME conjugate. Meanwhile,
we also observed a gradual increment of two additional new
peaks at tR 2.35 min and tR 5.72 min, corresponding to the
photoproduct (PP1) and chlorambucil (PP2) respectively
( Figure 3).
In order to see color change from green to blue the excitation of
the CBZ-DCV-CBL (5) at 380 nm produced a dual emission
peaks at 440 and 533 nm (CT emission) respectively. Gradual
addition of GSH to the solution of 5 results in gradual decrease
in the emission intensity at 533 nm with the concomitant
increase in the emission peak at 440 nm (Figure S13 in SI). It
was noted that the addition of 1.5 equivalent of GSH end up with
the complete quenching of the peak at 533 nm whereas the
maximum intensity at 440 nm was noted. Therefore the addition
of GSH to the solution of CBZ-DCV-CBL resulted complete
disappearance of the CT green emission and therefore the
localized π–π* transition with strong blue emission becomes the
only emissive band which could be clearly visible in naked eye
under the irradiation of a hand held UV-lamp at 365 nm.
Figure 3. HPLC overlay chromatogram of CBZ-DCV-CBL-ME conjugate at
different time intervals of light irradiation (0-60 min).
The light-induced release of the anticancer drug was then
quantified by plotting the HPLC peak area obtained for
chlorambucil vs. different irradiation times (Figure 4a). The
photolysis was followed until 90% of chlorambucil was released
from the CBZ-DCV-CBL-ME conjugate. Further, to demonstrate
the precise control over the drug release by light, we monitored
the release of chlorambucil by periodically switching the UV light
source on and off. Figure 4b clearly indicates that whenever the
light source was switched off, the drug release stopped, which
clearly indicates that external stimulus light only induces the
anticancer drug release. Further, we calculated the rate constant
(Kp) for the drug release and is found to be 2.59536 × 10-4 s-1.
From this, the photochemical quantum yield was calculated by
using potassium ferrioxalate as an actinometer and found to be
Фp= 0.099.
Further, to validate the above hypothesis, a model reaction
between CBZ-DCV-CBL and a thiol, 2-mercaptoethanol (ME)
was performed (Scheme 3) and the course of the reaction was
1
monitored by H NMR spectroscopy (Figure S14 in SI). Upon
addition of ME, the olefinic proton (Ha) of CBZ-DCV-CBL with
chemical shift of ~ 8.60 ppm vanished with the appearance of
two new peaks Hb at 5.08 ppm and Hc at 5.68 ppm which
confirms the thiol-ene addition reaction between the thiol group
and the dicyanovinyl group. Again, the mass spectral analysis
also shows the molecular ion peak of the addition product of
CBZ-DCV-CBL and ME (Figure S15 in SI) further support the
formation of addition product. Then we separated CBZ-DCV-
CBL-ME by reverse phase HPLC using acetonitrile as a mobile
phase. The fluorescence quantum yield (Φf) of CBZ-DCV-CBL-
ME in absolute ethanol was calculated using 9, 10-
Diphenylanthracene as the standard (Φf = 0.95 in ethanol) and
found to be Φf = 0.12.
Scheme 3. Model reaction between CBZ-DCV-CBL and 2-mercaptoethanol
Figure 4. (a) Amount of chlorambucil released by CBZ-DCV-CBL-ME at
different irradiation times (0-60 min) using UV light (λ≥365 nm), (b) progress of
the release of chlorambucil under bright and dark conditions (‘‘ON’’ indicates
the start of UV light irradiation and ‘‘OFF’’ indicates the end of UV light
irradiation.
(ME) in DMSO-d6.
To investigate the drug release ability from conjugate 5a, a
solution of CBZ-DCV-CBL-ME conjugate (1 × 10-4 M, 5 ml) in
ACN/PBS buffer (3:7 v/v) was irradiated with the 125 W medium
pressure Hg lamp as the source of UV light (λ ≥ 365 nm) using a
suitable UV cut-off filter (0.1 M CuSO4 solution) with continuous
stirring for 60 min.The release of the anticancer drug,
chlorambucil was monitored by RP-HPLC. The HPLC data
analysis demonstrates that, with increasing irradiation time,
there is a gradual decrease of the peak at tR 4.25 min, indicating
To investigate the cellular uptake property of CBZ-DCV-CBL and
Bio-CBZ-DCV-CBL, the cell imaging studies were performed by
HeLa cells. Confocal microscopy study confirms the
internalization of Bio-CBZ-DCV-CBL is more compare to CBZ-
DCV-CBL as observed from Figure 5 iib and iiib, ivb. The two
major features of DDS, (i) ability of biotin moiety guiding towards
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biotin receptor and (ii) responsiveness of the system towards
glutathione has been assessed here. Since, cancer cells highly
express glutathione and biotin receptors. The concept of
targeted delivery has been appreciably showed in case of Bio-
CBZ-DCV-CBL. The time dependent increase in internalization
of the DDS [increase in blue fluorescence – biotin moiety
targeting tumor cells (as shown in Figure 5 iiib and ivb)] and
reduction in green fluorescence – glutathione sensing (as shown
in Figure 5 iiic and ivc). The dual characteristic of the DDS
(Bio-CBZ-DCV-CBL) serves the purpose of targeting and
sensing, thus enhancing the internalization on tumor cells.
normal level of GSH present in NIH 3T3 cells reacted with Bio-
CBZ-DCV-CBL conjugate.
Figure 6. Confocal microscopy images of normal cells (NIH 3T3): (ia and iia)
Brightfield images; (ib) cells treated with Bio-CBZ-DCV-CBL after 2 h of
incubation: green emission illustrating internalization of Bio-CBZ-DCV-CBL
conjugate. (iib) cells treated with Bio-CBZ-DCV-CBL after 4 h of incubation
showing less reduction in green fluorescence compare to cancer cells (Scale
bar = 20 μm).
The in vitro anticancer activity was measured using the MTT (3-
(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide,22
a
yellow tetrazole) assay in HeLa cells. Different concentration of
compounds CBL, CBZ-DCV-CBL and Bio-CBZ-DCV-CBL were
added in the wells and subjected to photolysis. The percentages
of cell viability vs. concentration of compounds at a different time
interval before and after photolysis are presented in Figure 7a
and Figure 7b respectively. From results, it is evident that Bio-
CBZ-DCV-CBL after photolysis possesses potent anticancer
activity because of biotin receptor targeting and glutathione
sensing, in terms of cell viability. The CBL in Bio-CBZ-DCV-CBL
is able to target the cells efficiently in comparison to only CBL
and CBZ-DCV-CBL. From these results, it is clearly confirmed
that the biotin moiety and glutathione sensing plays a dual role
of targeting and sensing unit to tumor cells in this DDS.
Figure 5. Confocal microscopy images of HeLa cells: (i) untreated cells; (ii)
cells treated with CBZ-DCV-CBL after 2 h of incubation shows both blue and
green fluorescence illustrating internalization and glutathione sensing. (iii and
iv) cells treated with Bio-CBZ-DCV-CBL showing time dependent increase in
internalization of the DDS illustrating increase in blue fluorescence (iii b and iv
b)–biotin moiety targeting tumor cells and reduction in green fluorescence (iii c
and iv c) glutathione sensing). (Scale bar = 20 μm).
Further, to validate the concept of GSH sensing mediated
cancer cell detection over the normal cell, cell imaging was
performed with Bio-CBZ-DCV-CBL conjugate on normal cell line
NIH 3T3. NIH 3T3 cells were treated with Bio-CBZ-DCV-CBL for
2h and 4h respectively following the same conditions to that of
HeLa cells. Followed by confocal fluorescent images (Figure 6)
were taken which clearly displays that after 2h and 4h of
treatment Bio-CBZ-DCV-CBL conjugate was readily internalized.
From the Figure 6 it could be clearly observe that even after 4h
of treatment green emission from Bio-CBZ-DCV-CBL conjugate
was visible (Figure 6 iib) which is contrary to the images
obtained in case of cancerous HeLa cells where green emission
of Bio-CBZ-DCV-CBL conjugate was totally quencehed owing to
the already mentioned thiol-ene reaction. Therefore, the above
result clearly display that the Bio-CBZ-DCV-CBL conjugate can
precisely distinguish the cancer cells and the normal cells.
However, reduced intensity of green emission (Figure 6 iib) in
case of 4h incubation in comparison to 2h incubation (Figure 6
iia) is may be because of the same thiol-ene reaction where
Figure 7. (a−b) Cell viability assay of Bio-CBZ-DCV-CBL in HeLa cell line: (a)
before photolysis, (b) after photolysis. Values are presented as mean ± SD.
In conclusion, we have developed a new theranostic agent, Bio-
CBZ-DCV-CBL conjugate (6) and its synthesis, characterization,
spectroscopic properties and anticancer activity as well as
biological applications has been investigated. Upon addition of
free thiol to compound 6, the dicyanovinyl bond break down via
thiol-ene click reaction at pH < 7, restricting the intramolecular
charge transfer between donor and acceptor. This leads to
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[18] A. Paul, A. Jana, S. Karthik, M. Bera, Y. Zhao, N. D. P. Singh. J. Mater.
Chem. B, 2016, 4, 521-528.
change in fluorescence emission from green to blue and
facilitate releasing of the active drug CBL upon irradiation. The
confocal microscopic experiment reveals that the present
theranostic DDS effeciently internalized by the biotin receptor-
positive HeLa tumor cells, sense the intracellular thiols of cancer
microenvironment by thio-ene reaction and thereby reduces
resistance to chemotherapy drugs and showed increased
therapeutic effect. Therefore, our DDS demonstrated a new and
efficient strategy for the specific tumor targeted drug delivery
and tumor imaging.
[19] V. Hagen, S. Frings, J. Bendig, D. Lorenz, B. Wiesner, U. B. Kaupp,
Angew. Chem., Int. Ed. 2002, 41, 3625-3628.
[20] A. Jana, K. S. P. Devi, T. K. Maiti, N. D. P. Singh, J. Am. Chem. Soc.
2012, 134, 7656−7659.
[21] A. Jana, K. T. Nguyen, X. Li, P.Zhu, N. S. Tan, H. Ågren, Y. Zhao. ACS
Nano. 2014, 8, 5939-5952.
[22] I. Pal, K. K. Dey, M. Chaurasia, S. Parida, S. Das, Y. Rajesh, K. Sharma,
T. Chowdhury, M. Mandal. Tumour Biology. 2016, 37, 6389–6402.
Experimental Section
Experimental Details.
ACKNOWLEDGMENT
We thank DST (SERB) for financial support. DST-FIST for 600
and 400 MHz NMR. Y. V. is thankful to IIT KGP for the
fellowship. Y. R is thankful to DST INSPIRE (IF130658). A. J. is
thankful to DST, India for DST-INSPIRE Faculty Research
project grant (GAP 0546) at CSIR-IICT, Hyderabad.
Keywords: Carbazole • Photoremovable Protecting Group •
Tumour Targeted • Glutathione Sensing • Photoresponsive
Anticancer Drug Delivery
[1] (a) J. A. Kemp, M. S. Shim, C. Y. Heo, Y. J. Kwon. Adv. Drug Delivery
Rev. 2016, 98, 3-18. (b) M. C. Garnett. Adv. Drug Delivery Rev. 2001,
53, 171−216 (c) R. Mahato, W. Tai, K. Cheng. Adv. Drug Delivery Rev.
2011, 63, 659−670.
[2] K .Ariga, M. Naito, Q. Jiac, D. Payra. Cryst. Eng. Comm. 2016, 18, 4890–
4899.
[3] S. Mura, N. Julien, P.Couvreur. Nat. Mater. 2013, 12, 991-1003.
[4] Z. Yang, J. H. Lee, H. M. Jeon, J. H. Han, N. Park, Y. He, H. Lee, K. S.
Hong, C. Kang, J. S. Kim. J. Am. Chem. Soc. 2013, 135, 11657−11662.
[5] S. Maiti, N. Park, J. H. Han, H. M. Jeon, J. H. Lee, S. Bhuniya, C. Kang, J.
S. Kim. J. Am. Chem. Soc. 2013, 135, 4567−4572.
[6] S. Karthik, B. N. P. Kumar, M. Gangopadhyay, M. Mandal, N. D. P. Singh.
J. Mater. Chem. B, 2015, 3, 728–732.
[7] M. H. Lee, J. H. Han, P.-S. Kwon, S. Bhuniya, J. Y. Kim, J. L. Sessler, C.
Kang, J. S. Kim. J. Am. Chem. Soc. 2012, 134, 1316−1322.
[8] M. H. Lee, Z. Yang, C. W. Lim, Y. H. Lee, S. Dongbang, C. Kang, J. S. Kim.
Chem. Rev. 2013, 113, 5071−5109.
[9] B. S. Murray, M. V. Babak, C. G. Hartinger, P. J. Dyson, Coord. Chem.
Rev. 2016, 306, 86-114.
[10] M. H. Lee, J. H. Han, J.-H. Lee, H. G. Choi, C. Kang, J. S .Kim. J. Am.
Chem. Soc. 2012, 134, 17314−17319.
[11] T. Legigan, J. Clarhaut, I. T. Opalinski, A. Monvoisin, B. Renoux, M.
Thomas, A. L. Pape, S. Lerondel, S. Papot. Angew. Chem., Int. Ed.
2012, 51, 11606−11610.
[12] Y. Li, W. Xiao, K. Xiao, L. Berti, J. Luo, H. P. Tsent, G. Fung, K. S. Lam.
Angew. Chem., Int. Ed. 2012, 51, 2864−2869.
[13] F. Mahammud, M. Guo, W. Qi, F. Sun, A. Wang, Y. Guo, G. Zhu, J. Am.
Chem. Soc. 2011, 133, 8778−8781.
[14] L. -Y. Niu, Y. -S. Guan, Y. -Z. Chen, L. -Z. Wu, C.-H. Tung, Q. -Z. Yang, J.
Am. Chem. Soc, 2012, 134, 18928.
[15] D. Zhai, S. -C. Lee, S. -W. Yunb, Y. -T. Chang, Chem. Commun, 2013, 49,
7207-7209.
[16] J. M. Estrela, A. Ortega, E. Obrador. Critical Reviews in Clinical
Laboratory Sciences, 2006, 43, 143–181.
[17] M. H. Lee, J. L. Sessler, J. S. Kim. Acc. Chem. Res. 2015, 48, 2935−2946.
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COMMUNICATION
COMMUNICATION
Yarra Venkatesh,[a] S. Karthik,[a]
Y. Rajesh,[b] Mahitosh
Mandal,[b] Avijit Jana,*[c, d] and
N. D. Pradeep Singh*[a]
Page No. 1 – Page No. 5
Three Arm, Biotin-tagged
Carbazole-Dicyanovinyl-
Chlorambucil
Simultaneous
Targetting,
Conjugate:
Tumor
Sensing
and
Photoresponsive Anticancer
Drug Delivery
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