Design and synthesis of parthenolide-SAHA hybrids for intervention of drug-resistant acute myeloid leukemia

Article abstract of DOI:10.1016/j.bioorg.2019.03.056

A series of parthenolide-SAHA hybrids were synthesized and evaluated for their anti-AML activities against HL-60 and HL-60/ADR cell lines. The most active compound 26 exhibited high activity against HL-60/ADR cell line with IC₅₀ value of 0.15 μ

Full text of DOI:10.1016/j.bioorg.2019.03.056

Accepted Manuscript
Design and Synthesis of Parthenolide- SAHA Hybrids for Intervention of Drug-
Resistant Acute Myeloid Leukemia
Weizhi Ge, Zhongquan Liu, Yu Sun, Tianpeng Wang, Hongyu Guo, Xinyi Chen,
Shengzu Li, Mengmeng Wang, Yue Chen, Yahui Ding, Quan Zhang
PII:
S0045-2068(18)30916-7
DOI:
https://doi.org/10.1016/j.bioorg.2019.03.056
YBIOO 2882
Reference:
To appear in:
Bioorganic Chemistry
Received Date:
Revised Date:
Accepted Date:
22 August 2018
15 January 2019
19 March 2019
Please cite this article as: W. Ge, Z. Liu, Y. Sun, T. Wang, H. Guo, X. Chen, S. Li, M. Wang, Y. Chen, Y. Ding, Q.
Zhang, Design and Synthesis of Parthenolide- SAHA Hybrids for Intervention of Drug-Resistant Acute Myeloid
Leukemia, Bioorganic Chemistry (2019), doi: https://doi.org/10.1016/j.bioorg.2019.03.056
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Design and Synthesis of Parthenolide-
SAHA Hybrids for Intervention of
Drug-Resistant Acute Myeloid Leukemia
a
a
b
a
a
a
Weizhi Ge, Zhongquan Liu, Yu Sun, Tianpeng Wang, Hongyu Guo, Xinyi Chen,
a
c
a,
a,
a,
Shengzu Li, Mengmeng Wang, Yue Chen, * Yahui Ding * and Quan Zhang *
a
State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy and
Tianjin Key Laboratory of Molecular Drug Research, Nankai University, Haihe
Education Park, 38 Tongyan Road, Tianjin 300353, People’s Republic of China
b
College of Life Sciences, Nankai University, Tianjin 300353, People’s Republic of
China
c
Accendatech Company, Ltd., Tianjin 300384, People's Republic of China
*
Corresponding authors:
Y.C.: yuechen@nankai.edu.cn
Y.D.: E-mail: 017095@nankai.edu.cn
Q.Z.: E-mail: zhangquan@nankai.edu.cn or zhangquan612@163.com
1

Abstract
A series of parthenolide-SAHA hybrids were synthesized and evaluated for their
anti-AML activities against HL-60 and HL-60/ADR cell lines. The most active
compound 26 exhibited high activity against HL-60/ADR cell line with IC50 value of
0
.15 μM, which demonstrated 16.8-fold improvement compared to that of the parent
compound PTL (IC50 = 2.52 μM). Moreover, it was six times more potent than the
reference drug SAHA (IC50 = 0.90 µM) and fifty-one times more potent than ADR
(
IC50 = 7.72 µM). The preliminary molecular mechanism of 26 indicated that
compound 26 could significantly induce apoptosis of HL-60/ADR cells. The effect of
compound 26 was mainly through mitochondria pathway. Further investigation
revealed that the protein level of HDAC1 and HDAC6 were reduced after the
treatment of compound 26 with a dose-dependent manner. Compound 26 could
significantly decrease ABCC1 expression, which increased the accumulation of
intracellular drug for overcoming the drug resistance. On the base of these results,
compound 26 might be considered as a promising candidate for further evaluation as a
potential anti-AML drug.
Keywords:
Parthenolide; SAHA; Hybrid; Histone deacetylase; Drug resistance
2

1
. Introduction
Acute myeloid leukemia (AML) is a malignant disease characterized by an
aberrant accumulation of immature myeloid hematopoietic cells [1,2]. Chemotherapy
is one of the common treatments, and most patients can get longer survival interval
through chemotherapy. But about 20 percent of patients will develop resistance after
chemotherapy, more than half of those will relapse [3–5]. Many leukemia cells will
not only develop resistance to specific drugs, but also cross-resistance to other types
of drugs, this phenomenon is defined as multidrug resistance (MDR), therefore most
of recurrent patients become insensitive to chemotherapeutic agents, eventually die of
the disease [5,6]. Relapse has become a major problem in the treatment of leukemia,
and drug resistance is an important cause of relapse [7–9]. The main cause of MDR is
over-expression of the P-glycoprotein or multidrug resistance-associated proteins,
which acts as drug efflux pump, lowering intracellular drug levels to sublethal
concentrations [10–13]. Therefore, reversion of MDR is an effective strategy to
effectively cure AML.
Histone deacetylases (HDACs) could remove acetyl groups from histones,
maintained the dynamic equilibrium in acetylation levels of both nucleosomal
histones and nonhistone proteins and played an important role in regulating cell
proliferation and differentiation [14,15]. Especially, HDAC1 upregulation promoted
multidrug resistance [16,17]. Hence, HDACs were considered to be effective targets
for treatment of cancer. Histone deacetylase inhibitors (HDACi) have become a new
class of anti-cancer drugs, HDACi could induce differentiation, cell cycle arrest and
3

apoptosis in various transformed cell lines [18,19], and several HDACis were
undergoing clinical trials for solid and hematological malignancies [20–22]. Recent
reports suggested that HDACi may modulate the multidrug resistance-1 gene
expression and reduce expression of P-glycoprotein [23–25]. Combination of HDACi
and chemotherapy drugs could inhibit multidrug resistance-associated drug export.
SAHA (Figure 1), an orally bioavailable inhibitor of HDAC1 and HDAC6 [26],
showed broad spectrum of anti-cancer effect. The combination of SAHA and
flavopiridol effectively enhanced the killing activity against multidrug resistant
neuroblastoma cell lines [27].
Parthenolide (PTL, Figure 1), a prominent sesquiterpene lactone originally
derived from Feverfew (Tanacetum parthenium), exhibited exceptional anti-cancer,
anti-inflammatory and other properties [28]. PTL could induce apoptosis of cancer
cells, while have no effect on normal cells [29]. A prodrug of PTL, DMAPT, has been
advanced into clinical trial for treatment of AML [30]. It was reported that PTL could
reverse doxorubicin resistance in human lung carcinoma A549 cells by attenuating
NF-κB activation and HSP70 up-regulation [31], and reverse resistance of
multidrug-resistant hepatic carcinoma [32]. PTL exhibited its anti-cancer through
targeting NF-κB, redox thiols or DNMT1 [29]. Moreover, PTL could specifically
deplete HDAC1 protein without affecting other class I/II HDACs, through
degradation of HDAC1 by ubiquitination/proteasomal [33].
Accordingly, herein, we reported the design (Figure 2), synthesis of a series of
PTL-SAHA hybrids, and evaluation of their anti-AML activities. The preliminary
4

structure-activity relationship was revealed. Compound 26 showed high activity
against adriamycin (ADR) resistant cell line HL-60/ADR cells. The most potent 26
could significantly induce apoptosis of HL-60/ADR cells. The preliminary molecular
mechanism of 26 was also investigated.
2
. Results and Discussion
2
.1 Chemistry
The hydroxamic acid moiety is the pharmacophore of SAHA, which is a
zinc-binding group (ZBG). In order to incorporate both pharmacophores of PTL and
SAHA activities into a single chemical entity, the hybrid molecules were designed as
shown in Figure 2. A series of hybrids were designed and synthesized by changing the
connecting linker between PTL and hydroxamic acid units. The preparation of
PTL-SAHA hybrids is illustrated in Schemes 1–5.
As show in Scheme 1–2, hybrids 5, 8, 14, 17 were firstly designed. The
intermediates 3 and 10 were readily obtained from suberic acid monomethyl ester and
7
-bromoheptanoic acid, according to a reported procedure [34]. Methylparaben and
intermediate 10 formed ether bonds under alkaline conditions to obtain compound 11.
Followed by ester hydrolysis, the intermediate acid 12 was obtained. Starting with the
natural product PTL, melampomagnolide B (MMB) was synthesized according to the
procedure previously reported by our group [35].
After all the key intermediates were in the hands, we posed to synthesize hybrids
5
, 8, 14, 17. Direct esterification of MMB with intermediate 3, followed by removal
5

of Trt by TFA and Et SiH afforded 5. MMB and p-aminobenzoic acid were reacted to
3
obtain compound 6 by Mitsunobo reaction, followed by coupling with intermediate 3,
removal of protecting group Trt to obtain 8. The acid 12 reacted with MMB, followed
by removal of Trt group to generate 14. Similarly, intermediate 15 was obtained by
Mitsunobu reaction, followed by coupling with 10 and removal of Trt to yield 17.
In order to explore the effect of chain length on the activity, we designed
compounds 20a–20c. Compounds 20a–20c were prepared according to the procedure
for synthesis of compound 17 by using different bromic acid as the starting materials
(
Scheme 3). Compounds 23a–23c were designed and synthesized for investigating the
effect of methoxy group(s) on the anti-AML activity. MMB reacted with different
substituted cinnamic acids through Mitsunobu reaction to get intermediates 21a–21c
then followed by coupling with 10 and removal of Trt to generate compounds
2
3a–23c.
We designed and synthesized compounds 26 and 29 to study the influence of
substitution position of hydroxamic acid moiety on inhibitory activity. MMB reacted
with O-coumaric acid and trans-3-coumaric acid to form intermediates 24 and 27
through the Mitunobu reaction, respectively. Intermediates 24 and 27 reacted with
intermediate 10 to form 25 and 28, then removal of protecting group Trt to obtain
hybrids 26 and 29, respectively.
In order to explore the effects of the PTL moiety on their anti-AML activities, we
designed compound 32, replacing PTL moiety with methyl group (Scheme 5).
Coupling of 30 and 10 gave 31, followed by removal of Trt to generate 32. In order to
6

explore the effect of α, β-unsaturated ester moiety on their anti-AML activities, we
designed compound 36 with reduction of the double bond in γ-butyrolactone moiety.
MMB was reduced by sodium borohydride to give compound 33, followed the similar
steps for preparation of 17 to generate compound 36. Esterification of MMB and
cinnamic acid gave compound 37 with trim of the hydroxamic acid moiety for study
the importance of hydroxamic acid moiety.
2
.2 Inhibitory activity of PTL-SAHA hybrids against AML cell lines
To evaluate the anti-cancer activity of the synthesized PTL-SAHA hybrids, all of
hybrids (5, 8, 14, 17, 20a–20c, 23a–23c, 26, 29, 32, 36 and 37) were tested for their
activities against human AML cell line HL-60 and ADR resistant cell line
HL-60/ADR with clinically used anticancer drugs ADR and SAHA as references. PTL
and MMB were also included for comparison. The results were summarized in Tables
1
and 2. The anti-AML activity of each compound was expressed as the concentration
of compound that achieved 50% inhibition (IC50) of HL-60 and HL-60/ADR cells.
The sensitivity ratio (SR) was determined as the ratio of IC50 value for HL-60 cells to
IC50 value for HL-60/ADR cells for evaluation of the sensitivity of HL-60/ADR cells
comparing to HL-60 cells. The bioactivity of each compound was evaluated by the
combination of its IC50 and SR.
As shown in Table 1, PTL and SAHA showed moderate activity against HL-60
and HL-60/ADR cell lines. The SR values of PTL and SAHA were 1.40 and 1.68. The
combination of PTL and SAHA did not increase the activity and the values of SR.
MMB, a derivative of PTL, was less potent than PTL for both HL-60 and
7

HL-60/ADR cell lines. Primarily designed hybrids 5 and 8 that combined PTL and
hydroxamic acid moiety with different linkers exhibited comparable anti-AML
activity against HL-60 cell line with PTL, MMB, and SAHA. However, for the
HL-60/ADR cell line, the activities of both compounds were decreased, especially
compound 8. When we connected the PTL and hydroxamic acid moiety by ether bond,
etc. compounds 14 (IC50 = 1.22±0.63 μM) and 17 (IC50 = 1.05±0.65 μM), they
displayed improved anti-AML activity against HL-60/ADR cell line compared with
PTL ((IC50 = 2.52±1.90 μM), and increased the values of SR. The SR value of
compound 17 was 2.77. Therefore, we chose compound 17 as a lead compound for
further modification.
As show in Table 2, for subseries 20a–20c, as the chain length increased, the
anti-AML activity decreased and the SR values increased. Introduction of methyloxy
group at the ortho-position (23a) of the benzene ring led to decrease of the activity
against HL-60/ADR cells, but when introduction of methyloxy group at the
meta-position (23b) of the benzene ring, which improved anti-AML potency to HL-60
and HL-60/ADR cells. Introduction of dimethyloxy groups (23c) at the meta-position
of the benzene ring further increased the activity against HL-60 and HL-60/ADR cells
with IC50 values of 0.39±0.04 μM and 0.29±0.11 μM, respectively. Then we studied
the influence of different substitution position of the hydroxamic acid moiety on
benzene ring. When the hydroxamic acid moiety was introduced at the meta-position
of the benzene ring, etc. compound 29 with IC50 values of 0.37±0.08 μM and 0.29±
0
.11 μM for HL-60 and HL-60/ADR cell lines, respectively, the anti-AML activity
8

against HL-60 and HL-60/ADR cells was greatly improved comparing to PTL and
SAHA. To our surprise, the activity for HL-60/ADR cells was further improved when
the hydroxamic acid moiety was introduced to ortho-position of the benzene ring, etc.
compound 26 with IC50 value of 0.15±0.05 μM for HL-60/ADR cell lines, which was
1
6.8-fold improvement compared to the parent compound PTL (IC50 = 2.52 µM). It is
worth to note that it was six times more potent than the reference drug SAHA (IC50
.90 µM) and fifty-one times more potent than ADR (IC50 = 7.72 µM).
=
0
Removal of the PTL moiety (32) or reduction of the double bond in
γ-butyrolactone moiety (36) led to complete loss of anti-cancer activity (IC50 > 20
μM). Compound 37 (IC50 = 0.85 µM) with trim of the hydroxamic acid moiety was
less potent than compound 26 (IC50 = 0.15 µM), and it had no selectivity for the
HL-60/ADR cell line (SR = 0.63).
The most potent compound 26 was selected for study of its preliminary
mechanism.
2
.3 Preliminary mechanism study of compound 26
In order to study whether the effect of compound 26 was led by inducing
apoptosis, cell apoptosis was detected by flow cytometry. As shown in Figure 3, the
percentage of apoptosis were 3.8±0.2%, 6.53±0.40%, 13.27±0.67 and 20.97±1.03%
after the treatment of compound 26 at different concentrations of 0, 0.2 µM, 0.5 µM
and 1 µM, respectively, for 48 h. The result demonstrated that compound 26 played its
anti-AML effect mainly by inducing apoptosis.
9

To investigate the mechanism of compound 26 induced apoptosis of HL60/ADR
cells, the mitochondrial signal pathway related protein level of Bax, Bcl-2,
Cytochrome C, Caspase 3, Caspase 9 and PARP were detected. From the result in
Figure 4, the pro-apoptotic protein Bax was clearly increased, while the anti-
apoptotic protein Bcl-2 was significantly decreased. The release of cytochrome C was
increased with a dose-dependent manner after the treatment of compound 26. The
released cytochrome C activated the cleavage of caspases to induce apoptosis. From
the result, the cleavage of caspase 3, caspase 9 and PARP were prominently increased.
To further reveal the mechanism of compound 26, western blot assay was
performed. As compound 26 was modified based on the structure of HDAC inhibitor
(
SAHA), the protein expression of HDAC1 and HDAC6 were detected. From the
result in Figure 5, the protein level of HDAC1 and HDAC6 were significantly
decreased after the treatment of compound 26 with a dose-dependent manner. The
MTT assay showed that compound 26 was more sensitive to HL60/ADR than HL60
cells, which was just opposite to ADR, a clinically used drug for treatment of AML. It
has been reported that ATP binding cassette subfamily is the major cause for drug
resistance in HL60/ADR cells. ABC transporters, as multidrug efflux pumps could
pump the intracellular drugs out which lead to multidrug resistance. From the result in
Figure 6A, the protein expression of ATP binding cassette subfamily C member 1
(
ABCC1) was higher in HL60/ADR than that in HL60 cells. Moreover, it was
reported that HDAC could increase the protein level of ABCC1. Therefore, we
speculated that compound 26 would inhibit the expression of ABCC1 to overcome
10

multidrug resistance. To verify this hypothesis, the protein expression of ABCC1 was
detected by western blot assay. As shown in Figure 6B, compound 26 could
significantly decrease ABCC1 expression, which increased the accumulation of
intracellular drug.
3
. Conclusion
In conclusion, a series of fourteen parthenolide-SAHA hybrids was synthesized
and evaluated for their anti-AML activities against HL-60 and HL-60/ADR cell lines.
The most active compound 26 showed high activity against HL-60/ADR cell line with
IC50 value of 0.15 μM, which demonstrated 16.8-fold improvement compared to that
of the parent compound PTL (IC50 = 2.52 μM). Moreover, it was six times more
potent than the reference drug SAHA (IC50 = 0.90 µM) and fifty-one times more
potent than ADR (IC50 = 7.72 µM). The preliminary molecular mechanism of 26
indicated that compound 26 could significantly induce apoptosis of HL-60/ADR cells.
The effect of compound 26 was mainly through mitochondria pathway. Further
investigation revealed that the protein level of HDAC1 and HDAC6 were reduced
after the treatment of compound 26 with a dose-dependent manner. Compound 26
could significantly decrease ABCC1 expression, which increased the accumulation of
intracellular drug for overcoming the drug resistance.
On the base of these results, compound 26 might be considered as a promising
candidate for further evaluation as a potential anti-AML drug.
4
. Experimental
11

4
.1 Chemistry
Unless otherwise mentioned, all reactions were carried out under a nitrogen
atmosphere with dry solvents under anhydrous conditions. Reactions were monitored
by thin-layer chromatography carried out on 0.25 mm Tsingdao silica gel plates
(
60F-254). Visualization was achieved using UV light, phosphomolybdic acid in
ethanol or potassium permanganate in water, each followed by heating. Tsingdao
silica gel (60, particle size 0.040–0.063 mm) was used for flash column
1
13
chromatography. NMR spectra were recorded with a 400 MHz ( H: 400 MHz, C:
1
00 MHz) spectrometer. Data are reported as follows: chemical shift, multiplicity (s =
singlet, d = doublet, t = triplet, q = quartet, br. = broad, m = multiplet), coupling
constants and integration.
4
.1.1 8-Oxo-8-((trityloxy) amino) octanoic acid (3)
Compound 3 was readily obtained from suberic acid monomethyl ester,
1
according to a reported procedure [36]. H NMR (400 MHz, MeOD-d
4
) δ 7.49 – 7.19
(
m, 15H), 2.20 (t, J = 7.4 Hz, 2H), 1.85 (t, J = 7.3 Hz, 1H), 1.55 – 1.43 (m, 2H), 1.34
1
3
–
1
1.11 (m, 5H), 1.09 – 0.99 (m, 2H); C NMR (100 MHz, MeOD-d ) δ 177.6, 173.2,
4
43.6, 130.4, 129.0, 128.7, 94.4, 34.9, 33.5, 29.8, 29.7, 26.2, 25.8; HRMS (ESI) calcd
+
for C27
H
29NNaO
4
[M+Na] 454.1989, found 454.1986.
4
1
8
.1.2
((1aR,7aS,10aS,10bS,E)-1a-Methyl-8-methylene-9-oxo-1a,2,3,6,7,7a,8,9,10a,
0b-decahydrooxireno[2',3':9,10]cyclodeca[1,2-b]furan-5-yl)methyl
-oxo-8-((trityloxy)amino)octanoate (4)
12

To a solution of MMB (80 mg, 0.3 mmol), EDCI (86.3 mg, 0.45 mmol), DMAP
1.2 mg, 0.01 mmol) and compound 3 (194.2 mg, 0.45 mmol) in CH Cl (1 mL) was
added Et N (62.5 μL, 0.45 mmol) at 0 °C. The mixture was stirred for 8 h at room
temperature. The reaction was quenched with saturated aqueous NaHCO and
extracted with CH Cl (3 × 15 mL). The combined organic layers were washed with
saturated brine, dried over Na SO , and concentrated to give an oily crude product,
(
2
2
3
3
2
2
2
4
which was purified on a silica gel column to yield compound 4 (145 mg, yield: 71%).
1
H NMR (400 MHz, CDCl ) δ 7.78 – 7.28 (m, 16H), 6.25 (d, J = 3.0 Hz, 1H), 5.68 (t,
3
J = 8.0 Hz, 1H), 5.54 (d, J = 2.7 Hz, 1H), 4.65 (d, J = 12.5 Hz, 1H), 4.44 (d, J = 12.5
Hz, 1H), 3.85 (t, J = 9.3 Hz, 1H), 2.87 (dd, J = 20.4, 10.5 Hz, 2H), 2.50 – 2.12 (m,
8
H), 1.71 – 1.62 (m, 1H), 1.60 (s, 2H), 1.57 – 1.50 (m, 5H), 1.25 (s, 5H), 1.15 – 1.06
1
3
(
m, 2H). C NMR (100 MHz, CDCl
3
) δ 173.5, 171.2, 169.5, 138.9, 135.1, 130.7,
1
2
7
29.2, 128.3, 120.4, 109.6, 100.1, 81.2, 66.6, 63.4, 60.1, 42.8, 36.8, 34.3, 32.1, 29.8,
+
8.9, 28.8, 25.9, 24.8, 24.6, 24.0, 18.1. HRMS (ESI) calcd for C42
00.3245, found 700.3250.
H
47NNaO [M+Na]
7
4
.1.3
((1aR,7aS,10aS,10bS,E)-1a-Methyl-8-methylene-9-oxo-1a,2,3,6,7,7a,8,9,10a,10b-dec
ahydrooxireno[2',3':9,10]cyclodeca[1,2-b]furan-5-yl)methyl
8
-(hydroxyamino)-8-oxooctanoate (5)
Compound 4 (86mg, 0.13 mmol) was dissolved in dichloromethane (2 mL). The
reaction mixture was then cooled in an ice bath and trifluoro acetic acid (TFA) and
13

triethylsilane (Et SiH) were added alternately dropwise until the yellow color
3
disappeared. Then the solvent was evaporated to give an oily crude product, which
1
was purified by a silica gel column to yield a yellow oil (40 mg, yield: 72%). H
NMR (400 MHz, MeOD-d4) δ 6.17 (d, J = 3.2 Hz, 1H), 5.67 (dd, J = 17.9, 5.4 Hz,
2
3
5
H), 4.70 (d, J = 12.6 Hz, 1H), 4.51 (d, J = 12.6 Hz, 1H), 4.03 (t, J = 9.3 Hz, 1H),
.05 (t, J = 8.7 Hz, 1H), 2.92 (d, J = 9.5 Hz, 1H), 2.59 – 2.06 (m, 10H), 1.62 (d, J =
13
.5 Hz, 4H), 1.56 (s, 3H), 1.35 (s, 5H), 1.08 (t, J = 12.8 Hz, 1H). C NMR (100 MHz,
) δ 175.1, 171.8, 141.0, 136.8, 131.2, 120.4, 82.9, 67.8, 64.8, 61.6, 43.9,
7.7, 35.0, 30.8, 30.8, 29.8, 29.8, 26.6, 26.5, 25.9, 25.5, 24.7, 18.1. HRMS (ESI)
MeOD-d
4
3
+
calcd for C23
H
33NNaO [M+Na] 458.2149, found 458.2154.
7
4
.1.4
(1aR,7aS,10aS,10bS,E)-1a-Methyl-8-methylene-9-oxo-1a,2,3,6,7,7a,8,9,10a,10b-dec
ahydrooxireno[2',3':9,10]cyclodeca[1,2-b]furan-5-yl)methyl 4-aminobenzoate (6)
(
To a solution of MMB (65.0 mg, 0.25 mmol), PPh
-aminobenzoic acid (33.8 mg, 0.25 mmol) in dry THF (2.5 mL) were added DIAD
49 μL, 0.25 mmol) under an Ar atmosphere at 0 °C. The reaction mixture was stirred
at room temperature for 8 h. Then, the reaction was quenched with saturated aqueous
NH Cl and extracted with EA (3 × 15 mL). The combined organic layers were washed
with saturated brine, dried over Na SO , and concentrated to give an oily crude
3
(64.5 mg, 0.25 mmol) and
4
(
4
2
4
product, which was purified on a silica gel column [PE/EA=2:1-1:2 ] to give
1
compound 6 as a yellow solid (90 mg, yield: 95%). H NMR (400 MHz, CDCl
3
) δ
7
.76 (d, J = 8.6 Hz, 2H), 6.57 (d, J = 8.6 Hz, 2H), 6.16 (d, J = 3.5 Hz, 1H), 5.69 (t, J =
14

8
1
2
3
1
2
3
.3 Hz, 1H), 5.45 (d, J = 3.2 Hz, 1H), 4.77 (d, J = 12.6 Hz, 1H), 4.60 (d, J = 12.6 Hz,
H), 4.05 (d, J = 7.0 Hz, 2H), 3.80 (t, J = 9.3 Hz, 1H), 2.92 (dd, J = 14.8, 5.8 Hz, 1H),
.84 (d, J = 9.4 Hz, 1H), 2.50 – 2.05 (m, 6H), 1.62 (dd, J = 16.4, 8.8 Hz, 1H), 1.49 (s,
1
3
H), 1.06 (t, J = 12.6 Hz, 1H); C NMR (100 MHz, CDCl ) δ 169.5, 166.3, 151.2,
3
38.6, 135.4, 131.7, 130.2, 120.5, 119.1, 113.8, 81.1, 66.5, 63.3, 60.1, 42.8, 36.7, 25.9,
+
4.7, 23.9, 18.1. HRMS (ESI) calcd for C22
84.1807.
H26NO
5
[M+H] 384.1805, found
4
.1.5
((1aR,7aS,10aS,10bS,E)-1a-Methyl-8-methylene-9-oxo-1a,2,3,6,7,7a,8,9,10a,10b-dec
ahydrooxireno[2',3':9,10]cyclodeca[1,2-b]furan-5-yl)methyl
4
-(8-oxo-8-((trityloxy)amino)octanamido)benzoate (7)
Compound 3 (80.9 mg, 0.19 mmol) and HATU (95.1 mg, 0.25 mmol) was
dissolved in dry DMF (4 mL), then DIPEA (44 μL, 0.25 mmol) was added. The
mixture was stirred at 40 °C for 1h, then compound 6 (48.0 mg, 0.13mmol) was added.
The reaction was stirred for 2h at this temperature. Then, the reaction was quenched
with saturated aqueous NH
4
Cl and extracted with EA (3 × 15 mL). The combined
SO , and concentrated
organic layers were washed with saturated brine, dried over Na
2
4
to give an oily crude product, which was purified on a silica gel column
1
[
PE/EA=3:1-1:1 ] to give compound 7 as a yellow solid (81 mg, yield: 78%). H
NMR (400 MHz, CDCl
3
) δ 7.94 (d, J = 8.7 Hz, 2H),7.64 (d, J = 8.0 Hz, 2H), 7.52 –
.27 (m, 16H), 6.20 (d, J = 3.5 Hz, 1H), 5.76 (t, J = 8.3 Hz, 1H), 5.51 (d, J = 3.1 Hz,
H), 4.87 (d, J = 12.5 Hz, 1H), 4.70 (d, J = 12.6 Hz, 1H), 3.86 (t, J = 9.3 Hz, 1H),
7
1
15

3
.03 – 2.92 (m, 1H), 2.89 (d, J = 9.4 Hz, 1H), 2.51 – 2.12 (m, 8H), 1.89 (s, 1H), 1.63
13
(
dd, J = 14.7, 7.3 Hz, 3H), 1.55 (s, 3H), 1.25 (s, 7H), 1.12 (t, J = 12.7 Hz, 2H). C
NMR (100 MHz, CDCl
3
) δ 177.5, 172.2, 169.6, 166.0, 138.7, 135.2, 130.9, 130.6,
1
2
7
29.1, 128.3, 128.1, 128.1, 128.0, 120.6, 119.0, 81.2, 67.0, 63.4, 60.2, 42.9, 36.8, 29.8,
+
8.5, 25.9, 25.1, 24.7, 24.0, 18.1. HRMS (ESI) calcd for C49
97.3796, found 797.3781.
H
53
N
2
8
O [M+H]
4
.1.6((1aR,7aS,10aS,10bS,E)-1a-Methyl-8-methylene-9-oxo-1a,2,3,6,7,7a,8,9,10a,10b
-
decahydrooxireno[2',3':9,10]cyclodeca[1,2-b]furan-5-yl)methyl
4
-(8-(hydroxyamino)-8-oxooctanamido)benzoate (8)
Compound 4 (81 mg, 0.10 mmol) was dissolved in dichloromethane (2 mL). The
reaction mixture was then cooled in an ice bath. TFA and Et SiH were added
3
alternately dropwise until the yellow color disappeared. Then the solvent was
evaporated to give an oily crude product, which was purified by a silica gel column to
1
yield a yellow oil (45 mg, yield: 80%). H NMR (400 MHz, MeOD-d
4
) δ 8.00 (d, J =
8
1
4
6
1
1
3
.2 Hz, 2H), 7.74 (d, J = 8.3 Hz, 2H), 6.18 (d, J = 3.4 Hz, 1H), 5.81 (t, J = 8.3 Hz,
H), 5.66 (d, J = 3.1 Hz, 1H), 4.95 (d, J = 12.7 Hz, 1H), 4.79 (d, J = 12.7 Hz, 1H),
.07 (t, J = 9.3 Hz, 1H), 3.19 – 3.07 (m, 1H), 2.99 (d, J = 9.5 Hz, 1H), 2.65 – 2.37 (m,
H), 2.30 – 2.10 (m, 4H), 1.83 – 1.63 (m, 5H), 1.60 (s, 3H), 1.44 (d, J = 2.9 Hz, 4H),
1
3
.13 (t, J = 13.0 Hz, 1H). C NMR (100 MHz, MeOD-d ) δ 174.9, 171.8, 167.4,
4
44.8, 140.8, 136.8, 131.6, 131.3, 126.1, 120.6, 120.2, 82.9, 68.2, 64.8, 61.6, 43.9,
8.0, 37.7, 33.6, 30.7, 29.9, 29.8, 26.6, 26.5, 25.6, 24.7, 18.1. HRMS (ESI) calcd for
+
C
30
H
39
N
2
O
8
[M+H] 555.2701, found 555.2703.
16

4
.1.7 7-Bromo-N-(trityloxy)heptanamide (10)
Compound 9 (500 mg, 2.39 mmol) was dissolved in 20 mL dry tetrahydrofuran,
followed by the addition of N-methylmorpholine (289 μL, 2.63 mmol). The solution
was then cooled to 10 °C and isobutyl chloroformate (341 μL, 2.63 mmol) was added.
After stirring for 5min, O-(triphenylmethyl) hydroxylamine (658mg, 2.39 mmol) was
added and the reaction mixture was stirred overnight. The precipitate formed was
filtered and the solvent evaporated under reduced pressure. The obtained product was
dissolved in ethyl acetate and extracted with saturated solution of NaHCO
3
and brine.
The combined organic layers were dried over Na SO and evaporated under reduced
2
4
pressure. The crude product was purified by flash chromatography using a mixture of
1
PE/EA=5:1-4:1 to yield a white solid (1.07 g, yield: 95%). H NMR (400 MHz,
CDCl ) δ 7.80 (s, 1H), 7.34-7.48 (m, 15H), 3.35 (t, J = 5.8 Hz, 2H), 1.75-1.86 (m 3H),
3
1
3
1
1
.61 (s, 1H), 1.44 (s, 1H), 1.27 (s, 3H), 1.07 (s, 2H). C NMR (100 MHz, CDCl ) δ
3
77.2, 141.2, 129.1, 128.2, 93.4, 33.9, 32.5, 31.1, 29.8, 28.2, 27.8, 23.3. HRMS (ESI)
+
calcd for C26
H
28BrNNaO
2
[M+Na] 488.1196, found 488.1201.
4
.1.8 Methyl 4-((7-oxo-7-((trityloxy) amino) heptyl) oxy) benzoate (11)
To a solution of compound 10 (1.63 g, 3.5 mmol) and methyl 4-hydroxybenzoate
152 mg, 1 mmol) in dry DMF 15 mL, K CO (552 mg, 4 mmol) was added. The
(
2
3
mixture was stirred at 40 °C for 4 h. The reaction was quenched with saturated
aqueous NaCl and extracted with EA (3 × 15 mL). The combined organic layers were
washed with saturated brine, dried over Na
2
SO , and concentrated to give an oily
4
17

crude product, which was purified on a silica gel column [PE/EA=3:1-1:1 ] to give
1
compound 11 as a yellow solid (473 mg, yield: 88% ). H NMR (400 MHz, CDCl
3
) δ
7
.97 (d, J = 7.7 Hz, 2H), 7.40 (d, J = 55.4 Hz, 16H), 6.88 (d, J = 8.0 Hz, 2H), 3.95 (t,
J = 6.0 Hz, 2H), 3.88 (s, 3H), 1.77 – 1.54 (m, 5H), 1.31 (d, J = 17.6 Hz, 3H), 1.10 (s,
1
3
2
1
H). C NMR (100 MHz, CDCl ) δ 177.2, 167.1, 163.0, 141.2, 131.7, 129.2, 128.3,
3
22.5, 114.2, 100.1, 68.1, 52.0, 31.2, 29.8, 29.0, 28.9, 25.8, 23.5. HRMS (ESI) calcd
+
for C34
H
35NNaO
5
[M+Na] 560.2407, found 560.2412.
4
.1.9 4-((7-Oxo-7-((trityloxy)amino)heptyl)oxy)Benzoic acid (12)
Compound 11 (509 mg, 0.95 mmol) was dissolved in 9.4 mL THF-H O (1:1),
2
.
followed by the addition of LiOH H
2
O (795 mg, 1.89 mmol). The reaction mixture
was stirred at room temperature overnight. Upon completion, 2 N HCl was added to
acidify the reaction, and the solution was extracted with ethyl acetate three times. The
collected organic phase was washed with water and brine, and dried over anhydrous
Na
2
SO and evaporated under reduced pressure. The crude product was purified by
4
flash chromatography using a mixture of DCM: MeOH=60:1 to yield a white solid
1
(
355 mg, yield: 72%). H NMR (400 MHz, DMSO-d
6
) δ 12.58 (s, 1H), 10.16 (s, 1H),
7
.87 (d, J = 8.8 Hz, 2H), 7.30 (d, J = 9.3 Hz, 15H), 6.98 (d, J = 8.8 Hz, 2H), 3.97 (t, J
=
6.4 Hz, 2H), 1.78 (t, J = 6.6 Hz, 1H), 1.67 – 1.55 (m, 2H), 1.24 (q, J = 16.2 Hz, 5H),
1
3
1
1
.02 (d, J = 6.7 Hz, 2H); C NMR (100 MHz, DMSO-d ) δ 162.2, 142.5, 131.3,
6
28.9, 127.5, 127.4, 122.9, 114.2, 91.7, 67.6, 31.9, 28.9, 28.3, 28.0, 25.1, 24.6. HRMS
–
(
ESI) calcd for C33
H32NO
5
[M-H] 522.2286, found 522.2283.
18

4
.1.10
(1aR,7aS,10aS,10bS,E)-1a-Methyl-8-methylene-9-oxo-1a,2,3,6,7,7a,8,9,10a,10b-dec
ahydrooxireno[2',3':9,10]cyclodeca[1,2-b]furan-5-yl)methyl
(
4
-((7-oxo-7-((trityloxy)amino)heptyl)oxy)benzoate (13)
To a solution of MMB (28.5 mg, 0.11 mmol), DIC (33 mg, 0.16 mmol), DMAP
(
1.3 mg, 0.01 mmol) in dry DCM (1 mL), the compound 12 (56.5 mg, 0.11 mmol)
was added at 0 °C. The mixture was stirred for 8 h at room temperature. The reaction
was quenched with saturated aqueous NaHCO and extracted with DCM (3 × 15 mL).
The combined organic layers were washed with saturated brine, dried over Na SO ,
3
2
4
and concentrated to give an oily crude product, which was purified on a silica gel
1
column to yield compound 13 (50.8 mg, yield: 61%) as a white solid. H NMR (400
MHz, CDCl
H), 6.23 (d, J = 3.4 Hz, 1H), 5.77 (t, J = 8.3 Hz, 1H), 5.52 (d, J = 3.1 Hz, 1H), 4.87
d, J = 12.6 Hz, 1H), 4.70 (d, J = 12.6 Hz, 1H), 3.95 (t, J = 6.4 Hz, 2H), 3.86 (t, J =
3
) δ 7.95 (d, J = 8.8 Hz, 2H), 7.81 – 7.27 (m, 16H), 6.88 (d, J = 8.8 Hz,
2
(
9
1
.3 Hz, 1H), 2.98 (t, J = 9.0 Hz, 1H), 2.90 (d, J = 9.4 Hz, 1H), 2.52 – 2.14 (m, 6H),
.76 – 1.67 (m, 3H), 1.61 (s, 3H), 1.56 (s, 3H), 1.25 (s, 4H), 1.15 (d, J = 12.5 Hz, 2H).
1
3
C NMR (100 MHz, CDCl
3
) δ 177.3, 169.5, 166.2, 163.3, 141.2, 138.8, 135.3, 131.8,
1
2
30.5, 129.2, 128.3, 122.0, 120.6, 114.3, 81.2, 68.2, 66.8, 63.5, 60.1, 42.9, 36.8, 29.8,
9.5, 29.0, 28.9, 28.8, 26.0, 25.8, 24.7, 24.0, 18.2. HRMS (ESI) calcd for C48
H
50NO
8
–
[
M-H] 768.3542, found 768.3538.
4
.1.11
((1aR,7aS,10aS,10bS,E)-1a-Methyl-8-methylene-9-oxo-1a,2,3,6,7,7a,8,9,10a,10b-dec
19

ahydrooxireno[2',3':9,10]cyclodeca[1,2-b]furan-5-yl)methyl
4
-((7-(hydroxyamino)-7-oxoheptyl)oxy)benzoate (14)
Compound 13 (50 mg, 0.066 mmol) was dissolved in dichloromethane (2 mL).
The reaction mixture was then cooled in an ice bath. TFA and Et SiH were added
3
alternately dropwise until the yellow color disappeared. Then the solvent was
evaporated to give an oily crude product, which was purified by a silica gel column to
1
yield a colorless oil compound 14 (31 mg, yield: 89%). H NMR (400 MHz, CDCl
3
) δ
7
8
1
1
.94 (d, J = 8.3 Hz, 2H), 6.88 (d, J = 8.3 Hz, 2H), 6.20 (d, J = 2.9 Hz, 1H), 5.78 (t, J =
.3 Hz, 1H), 5.49 (d, J = 2.5 Hz, 1H), 4.86 (d, J = 12.6 Hz, 1H), 4.71 (d, J = 12.6 Hz,
H), 4.00 (s, 2H), 3.87 (t, J = 9.2 Hz, 1H), 3.00 (t, J = 9.7 Hz, 1H), 2.90 (d, J = 9.4 Hz,
H), 2.53 – 2.28 (m, 4H), 2.27 – 2.13 (m, 3H), 1.79 (s, 2H), 1.75 – 1.63 (m, 3H), 1.56
1
3
(
s, 3H), 1.25 (s, 5H), 1.13 (t, J = 12.8 Hz, 1H). C NMR (100 MHz, CDCl
3
) δ 169.6,
1
6
66.2, 163.3, 138.8, 135.3, 131.8, 130.9, 122.1, 120.6, 114.4, 81.2, 68.1, 67.0, 63.4,
0.2, 43.0, 36.8, 32.9, 32.1, 29.8, 28.9, 28.8, 26.0, 25.8, 25.0, 24.0, 18.2. HRMS (ESI)
+
calcd for C29
H
37NNaO
8
[M+Na] 550.2411, found 550.2414.
4
.1.12
(1aR,7aS,10aS,10bS,E)-1a-Methyl-8-methylene-9-oxo-1a,2,3,6,7,7a,8,9,10a,10b-dec
ahydrooxireno[2',3':9,10]cyclodeca[1,2-b]furan-5-yl)methyl
(
(E)-3-(4-hydroxyphenyl)acrylate(15)
To a solution of MMB (264 mg, 1.0 mmol), PPh (393 mg, 1.5 mmol) and
3
coumalic acid (210 mg, 1.5 mmol) in dry THF (10 mL) were added DIAD (0.3 mL,
20

1
.5 mmol) under an Ar atmosphere. The reaction mixture was stirred at room
temperature for 4 h. Then, the reaction was quenched with saturated aqueous NH Cl
and extracted with EA (3 × 15 mL). The combined organic layers were washed with
saturated brine, dried over Na SO , and concentrated to give an oily crude product,
4
2
4
which was purified on a silica gel column [PE/EA=2:1-1:2 ] to give compound 15
1
(
285 mg, yield: 69%) as a white solid. H NMR (400 MHz, CDCl
3
) δ 7.62 (d, J = 15.9
Hz, 1H), 7.38 (d, J = 8.5 Hz, 2H), 7.13-6.99 (m, 1H), 6.87 (d, J = 8.4 Hz, 2H), 6.26 (d,
J = 8.9 Hz, 1H), 6.23 (d, J = 3.6 Hz, 1H), 5.72 (t, J = 7.9 Hz, 1H), 5.57 (d, J = 3.3 Hz,
1
2
1
1
6
H), 4.76 (d, J = 12.5 Hz, 1H), 4.59 (d, J = 12.5 Hz, 1H), 3.89 (t, J = 9.3 Hz, 1H),
.98 (t, J = 9.1 Hz, 1H), 2.91 (d, J = 9.4 Hz, 1H), 2.51 – 2.11 (m, 6H), 1.73 – 1.64 (m,
1
3
H), 1.55 (s, 3H), 1.12 (t, J = 12.6 Hz, 1H). C NMR (100 MHz, CDCl
3
) δ 169.9,
67.3, 158.6, 145.7, 138.5, 134.9, 130.6, 130.1, 126.3, 120.8, 116.0, 114.1, 81.2, 66.8,
3.3, 60.3, 42.6, 36.5, 25.8, 24.5, 23.8, 17.9. HRMS (ESI) calcd for C24
H30NO
6
+
[
M+NH
4
] 428.2068, found 428.2067.
4
.1.13
((1aR,7aS,10aS,10bS,E)-1a-Methyl-8-methylene-9-oxo-1a,2,3,6,7,7a,8,9,10a,10b-dec
ahydrooxireno[2',3':9,10]cyclodeca[1,2-b]furan-5-yl)methyl
(E)-3-(4-((7-oxo-7-((trityloxy)amino)heptyl)oxy)phenyl)acrylate (16)
To a solution of compound 10 (517 mg, 1.11 mmol) and compound 15 (130 mg,
0
.32 mmol) in dry DMF 15 mL, K
2
CO (177 mg, 1.28 mmol) was added. The mixture
3
was stirred at 40 °C for 4 h. The reaction was quenched with saturated brine and
extracted with EA (3 × 15 mL). The combined organic layers were washed with
21

saturated brine, dried over Na
which was purified on a silica gel column [PE/EA=2:1-1:1 ] to give compound 16 as a
yellow solid (181 mg, yield: 71%). H NMR (400 MHz, CDCl ) δ 7.79 – 7.58 (m, 2H),
.54 – 7.27 (m, 17H), 6.88 (d, J = 7.8 Hz, 2H), 6.27 (d, J = 16.4 Hz, 2H), 5.74 (t, J =
2
SO
4
, and concentrated to give an oily crude product,
3
7
7
2
2
.6 Hz, 1H), 5.56 (s, 1H), 4.78 (d, J = 12.5 Hz, 1H), 4.59 (d, J = 12.5 Hz, 1H), 3.93 (s,
H), 3.87 (t, J = 9.3 Hz, 1H), 2.99 (t, J = 9.6 Hz, 1H), 2.90 (d, J = 9.3 Hz, 1H), 2.56 –
.30 (m, 4H), 2.30 – 2.13 (m, 2H), 1.77 – 1.59 (m, 5H), 1.56 (s, 3H), 1.31 (d, J = 17.5
1
3
Hz, 3H), 1.26 (s, 2H), 1.18 – 1.09 (m, 2H). C NMR (100 MHz, CDCl
67.0, 161.2, 145.4, 141.1, 138.8, 135.2, 130.6, 129.9, 129.0, 128.1, 126.7, 120.3,
14.9, 114.6, 114.0, 81.1, 68.0, 66.7, 63.3, 60.0, 42.8, 36.7, 29.7, 28.9, 28.7, 25.9,
3
) δ 169.4,
1
1
–
2
7
5.6, 24.7, 23.9, 18.0. HRMS (ESI) calcd for C50
94.3695.
H
52NO [M-H] 794.3693, found
8
4
.1.14
((1aR,7aS,10aS,10bS,E)-1a-Methyl-8-methylene-9-oxo-1a,2,3,6,7,7a,8,9,10a,10b-dec
ahydrooxireno[2',3':9,10]cyclodeca[1,2-b]furan-5-yl)methyl
(E)-3-(4-((7-(hydroxyamino)-7-oxoheptyl)oxy)phenyl)acrylate(17)
Compound 16 (106 mg, 0.13 mmol) was dissolved in dichloromethane (2 mL).
The reaction mixture was then cooled in an ice bath. TFA and Et SiH were added
3
alternately dropwise until the yellow color disappeared. Then the solvent was
evaporated to give an oily crude product, which was purified by a silica gel column to
1
yield a colorless oil compound 17 (60 mg, yield: 82%). H NMR (400 MHz, CDCl
3
) δ
8
.65 (s, 1H), 7.63 (d, J = 16.0 Hz, 1H), 7.43 (d, J = 7.5 Hz, 2H), 6.87 (d, J = 7.8 Hz,
22

2
H), 6.26 (d, J = 14.9 Hz, 2H), 5.74 (t, J = 8.2 Hz, 1H), 5.56 (s, 1H), 4.76 (d, J = 12.5
Hz, 1H), 4.59 (d, J = 12.6 Hz, 1H), 3.96 (s, 2H), 3.87 (t, J = 9.3 Hz, 1H), 3.01 (t, J =
0.3 Hz, 1H), 2.90 (d, J = 9.4 Hz, 1H), 2.50 – 2.15 (m, 8H), 1.77 (s, 2H), 1.72 – 1.64
1
1
3
(
m, 3H), 1.56 (s, 3H), 1.46 (s, 2H), 1.42 – 1.36 (m, 2H), 1.17 – 1.09 (m, 1H). C
NMR (100 MHz, CDCl
3
) δ169.7 (2C), 167.2, 161.3, 145.5, 138.9, 135.3, 130.9, 130.0,
1
2
26.8, 120.6, 115.1, 114.7, 81.3, 68.1, 67.0, 63.5, 60.2, 42.9, 36.8, 32.1, 29.8, 29.0,
–
8.9, 26.1, 25.8, 24.9, 24.0, 18.2. HRMS (ESI) calcd for C31
H
38NO [M-H] 552.2603,
8
found 552.2600.
4
.1.15 General procedure for the synthesis of compounds 18a–18c
Different acid (2.0 mmol, 1 eq) was dissolved in 40 mL dry tetrahydrofuran,
followed by the addition of N-methylmorpholine (2.2 mmol, 1.1 eq). The solution was
then cooled to 10 °C and isobutyl chloroformate (2.2 mmol, 1.1 eq) was added. After
stirring for 5min, O-(triphenylmethyl) hydroxylamine (2.2 mmol, 1.1 eq) was added
and the reaction mixture was stirred overnight. The precipitate formed was filtered
and the solvent evaporated under reduced pressure. The obtained product was
dissolved in ethyl acetate and extracted with saturated solution of NaHCO
3
and brine.
The combined organic layers were dried over Na SO and evaporated under reduced
2
4
pressure. The crude product was purified by flash chromatography using a mixture of
PE/EA=5:1-4:1 to yield a white solid 18a–18c.
4
.1.15.1 6-Bromo-N-(trityloxy)hexanamide (18a): White amorphous solid (yield:
1
9
0%). H NMR (400 MHz, DMSO-d
6
) δ 10.18 (s, 1H), 7.33 (s, 15H), 3.41 (t, J = 6.4
23

Hz, 2H), 1.79 (s, 2H), 1.70 – 1.59 (m, 2H), 1.26 – 1.16 (m, 2H), 1.09 (d, J = 6.1 Hz,
1
3
2
3
H). C NMR (100 MHz, DMSO-d
6
) δ 170.1, 142.4, 128.9, 127.5, 127.4, 91.7, 34.8,
+
1.9, 31.7, 26.9, 23.8. HRMS (ESI) calcd for C25
H
26BrNNaO
2
[M+Na] 474.1039,
found 474.1042.
4
.1.15.2 8-Bromo-N-(trityloxy)octanamide (18b): White amorphous solid (yield:
1
8
7%). H NMR (400 MHz, DMSO-d
6
) δ 10.13 (s, 1H), 7.33 (s, 15H), 3.50 (t, J = 6.7
Hz, 2H), 1.83 – 1.70 (m, 3H), 1.35 – 1.22 (m, 3H), 1.22 – 1.03 (m, 4H), 0.97 (d, J =
1
3
6
1
.8 Hz, 2H). C NMR (100 MHz, DMSO-d ) δ 170.3, 142.5, 128.9, 127.7, 127.5,
6
27.4, 126.6, 91.7, 35.1, 32.1, 28.1, 27.7, 27.3. HRMS (ESI) calcd for
+
C
27
H30BrNNaO
2
[M+Na] 502.1352, found 502.1358.
4
.1.15.3 9-Bromo-N-(trityloxy)nonanamide (18c): White amorphous solid (yield:
1
9
5%). H NMR (400 MHz, DMSO-d
6
) δ 12.43 (s, 1H), 9.62 (s, 15H), 5.79 (t, J = 6.0
Hz, 2H), 4.06 (d, J = 5.8 Hz, 4H), 3.66 – 3.56 (m, 2H), 3.46 (t, J = 24.8 Hz, 6H), 3.25
1
3
(
d, J = 5.3 Hz, 2H). C NMR (100 MHz, DMSO-d
6
) δ 170.3, 142.5, 128.9, 127.5,
1
27.4, 91.7, 35.2, 32.2, 32.0, 28.5, 28.2, 27.9, 27.4, 24.7. HRMS (ESI) calcd for
+
C
28
H
32BrNNaO [M+Na] 516.1509, found 516.1512.
2
4
.1.16 General procedure for the synthesis of compounds 19a–19c.
To a solution of compound 19a–19c (0.85 mmol, 3.5 eq) and compound 15 (100
mg, 0.24 mmol, 1 eq) in dry DMF 15 mL, K
2
CO (132.7 mg, 0.96 mmol, 4 eq) was
3
added. The mixture was stirred at 40 °C for 4 h. The reaction was quenched with
saturated brine and extracted with EA (3 × 15 mL). The combined organic layers were
24

washed with saturated brine, dried over Na
2
SO , and concentrated to give an oily
4
crude product, which was purified on a silica gel column [PE/EA=2:1-1:1 ] to give
compound 19a–19c as a yellow solid.
4
.1.16.1
(1aR,7aS,10aS,10bS,E)-1a-Methyl-8-methylene-9-oxo-1a,2,3,6,7,7a,8,9,10a,10b-dec
ahydrooxireno[2',3':9,10]cyclodeca[1,2-b]furan-5-yl)methyl
(
(E)-3-(4-((6-oxo-6-((trityloxy)amino)hexyl)oxy)phenyl)acrylate(19a):
White
1
amorphous solid (yield: 81%). H NMR (400 MHz, CDCl
3
) δ 7.65 (d, J = 15.9 Hz,
1
H), 7.44 (d, J = 8.5 Hz, 5H), 7.33 (s, 13H), 6.87 (d, J = 8.2 Hz, 2H), 6.27 (t, J = 9.5
Hz, 2H), 5.74 (t, J = 8.0 Hz, 1H), 5.56 (d, J = 2.9 Hz, 1H), 4.78 (d, J = 12.5 Hz, 1H),
4
9
1
1
1
1
.59 (d, J = 12.6 Hz, 1H), 3.94 – 3.82 (m, 3H), 2.99 (t, J = 8.9 Hz, 1H), 2.89 (d, J =
.4 Hz, 1H), 2.53 – 2.12 (m, 7H), 1.67 (s, 6H), 1.56 (s, 3H), 1.31 (d, J = 19.8 Hz, 2H),
1
3
.17 – 1.09 (m, 1H). C NMR (100 MHz, CDCl ) δ 177.1, 169.5, 167.1, 161.3, 145.5,
3
41.3, 138.9, 135.3, 130.7, 130.0, 129.2, 128.3, 126.8, 120.5, 115.0, 114.7, 114.1,
00.1, 81.2, 67.9, 66.9, 63.5, 60.1, 42.9, 36.8, 29.8, 29.8, 28.9, 26.0, 25.6, 24.8, 24.0,
+
8.1. HRMS (ESI) calcd for C49
H
51NNaO
8
[M+Na] 804.3507, found 804.3510.
4
.1.16.2
(8-(4-((E)-3-(((1aR,7aS,10aS,10bS,E)-1a-Methyl-8-methylene-9-oxo-1a,2,3,6,7,7a,8,9
,
10a,10b-decahydrooxireno[2',3':9,10]cyclodeca[1,2-b]furan-5-yl)methoxy)-3-oxopro
p-1-en-1-yl)phenoxy)octanoyl)(trityloxy)amide(19b): White amorphous solid (yield:
1
7
7%). H NMR (400 MHz, CDCl
3
) δ 7.74 (s, 1H), 7.65 (d, J = 15.8 Hz, 1H), 7.45 (d,
J = 8.2 Hz, 4H), 7.33 (s, 13H), 6.88 (d, J = 7.9 Hz, 2H), 6.27 (d, J = 15.5 Hz, 2H),
25

5
1
.74 (t, J = 8.0 Hz, 1H), 5.56 (s, 1H), 4.78 (d, J = 12.4 Hz, 1H), 4.59 (d, J = 12.5 Hz,
H), 3.95 (t, J = 5.3 Hz, 2H), 3.87 (t, J = 9.2 Hz, 1H), 2.99 (t, J = 10.2 Hz, 1H), 2.90
(
d, J = 9.3 Hz, 1H), 2.54 – 2.11 (m, 6H), 1.79 – 1.68 (m, 3H), 1.61 (d, J = 18.0 Hz,
1
3
3
H), 1.56 (s, 3H), 1.43 – 1.32 (m, 3H), 1.25 (s, 3H), 1.17 – 1.09 (m, 2H). C NMR
(
100 MHz, CDCl
3
) δ 169.5, 167.1, 161.4, 145.5, 141.2, 138.9, 135.3, 130.8, 130.0,
1
4
29.9, 129.2, 128.2, 127.8, 126.8, 120.5, 115.0, 114.7, 81.2, 68.2, 66.9, 63.5, 60.1,
2.9, 36.8, 29.8, 29.2, 29.1, 26.0, 25.9, 24.8, 24.0, 18.2. HRMS (ESI) calcd for
–
C
51
H54NO
8
[M-H] 808.3855, found 808.3853.
4
.1.16.3
(1aR,7aS,10aS,10bS,E)-1a-Methyl-8-methylene-9-oxo-1a,2,3,6,7,7a,8,9,10a,10b-dec
ahydrooxireno[2',3':9,10]cyclodeca[1,2-b]furan-5-yl)methyl
(
(E)-3-(4-((9-oxo-9-((trityloxy)amino)nonyl)oxy)phenyl)acrylate
(19c)
White
1
amorphous solid (yield: 86%). H NMR (400 MHz, CDCl
3
) δ 7.65 (d, J = 15.9 Hz,
1
H), 7.54 – 7.27 (m, 18H), 6.89 (d, J = 8.3 Hz, 2H), 6.26 (t, J = 10.1 Hz, 2H), 5.74 (t,
J = 8.0 Hz, 1H), 5.56 (d, J = 2.6 Hz, 1H), 4.78 (d, J = 12.5 Hz, 1H), 4.59 (d, J = 12.6
Hz, 1H), 3.96 (t, J = 6.4 Hz, 2H), 3.87 (t, J = 9.3 Hz, 1H), 2.98 (t, J = 9.0 Hz, 1H),
2
.89 (d, J = 9.4 Hz, 1H), 2.52 – 2.12 (m, 6H), 1.74 (dd, J = 19.4, 11.9 Hz, 3H), 1.54
(
(
d, J = 14.7 Hz, 4H), 1.39 (d, J = 7.0 Hz, 3H), 1.23 (d, J = 22.6 Hz, 6H), 1.17 – 1.08
1
3
m, 3H). C NMR (100 MHz, CDCl
3
) δ 177.4, 169.5, 167.1, 161.3, 145.5, 141.2,
1
8
38.9, 135.3, 130.7, 129.9, 129.1, 128.2, 127.7, 127.4, 126.7, 120.4, 115.0, 114.6,
1.2, 68.2, 66.8, 63.4, 60.1, 42.8, 36.8, 29.8, 29.2, 29.1, 26.0, 24.7, 24.0, 18.1. HRMS
–
(
ESI) calcd for C52
H56NO
8
[M-H] 822.4011, found 822.4008.
26

4
.1.17 General procedure for the synthesis of compounds 20a–20c
Compound 19a–19c (85 mg) was dissolved in dichloromethane (2 mL). The
reaction mixture was then cooled in an ice bath. TFA and Et SiH were added
3
alternately dropwise until the yellow color disappeared. Then the solvent was
evaporated to give an oily crude product, which was purified by a silica gel column to
yield a colorless oil compound 20a–20c.
4
.1.17.1
(1aR,7aS,10aS,10bS,E)-1a-Methyl-8-methylene-9-oxo-1a,2,3,6,7,7a,8,9,10a,10b-dec
ahydrooxireno[2',3':9,10]cyclodeca[1,2-b]furan-5-yl)methyl
(
(E)-3-(4-((6-(hydroxyamino)-6-oxohexyl)oxy)phenyl)acrylate(20a): White amorphous
1
solid (yield: 83%). H NMR (400 MHz, CDCl
3
) δ 9.36 (s, 1H), 7.60 (d, J = 15.9 Hz,
1
H), 7.40 (d, J = 8.5 Hz, 2H), 6.84 (d, J = 8.5 Hz, 2H), 6.29 – 6.17 (m, 2H), 5.71 (t, J
=
8.0 Hz, 1H), 5.54 (d, J = 3.0 Hz, 1H), 4.74 (d, J = 12.5 Hz, 1H), 4.58 (d, J = 12.6
Hz, 1H), 3.96 – 3.81 (m, 3H), 3.00 (t, J = 8.8 Hz, 1H), 2.88 (d, J = 9.4 Hz, 1H), 2.47 –
2
1
1
6
.12 (m, 8H), 1.75 (dd, J = 16.1, 10.0 Hz, 2H), 1.68 (d, J = 7.4 Hz, 3H), 1.54 (s, 3H),
1
3
.44 (s, 2H), 1.10 (t, J = 12.5 Hz, 1H). C NMR (100 MHz, CDCl ) δ 169.8(2C),
3
67.1, 161.1, 145.4, 138.8, 135.1, 130.8, 130.0, 126.7, 120.6, 115.0, 114.7, 81.3, 67.8,
7.0, 63.4, 60.3, 42.8, 36.7, 32.7, 28.8, 26.0, 25.5, 25.1, 24.9, 23.9, 18.1. HRMS (ESI)
–
calcd for C30
H36NO
8
[M-H] 538.2446, found 538.2442.
4
.1.17.2
((1aR,7aS,10aS,10bS,E)-1a-Methyl-8-methylene-9-oxo-1a,2,3,6,7,7a,8,9,10a,10b-dec
27

ahydrooxireno[2',3':9,10]cyclodeca[1,2-b]furan-5-yl)methyl
(E)-3-(4-((8-(hydroxyamino)-8-oxooctyl)oxy)phenyl)acrylate (20b): White amorphous
1
solid (yield: 87%). H NMR (400 MHz, CDCl
3
) δ 7.60 (t, J = 16.9 Hz, 1H), 7.42 (d, J
=
8.2 Hz, 2H), 6.86 (d, J = 8.1 Hz, 2H), 6.25 (d, J = 15.8 Hz, 2H), 5.72 (t, J = 8.1 Hz,
1
3
9
H), 5.55 (d, J = 2.4 Hz, 1H), 4.73 (t, J = 15.5 Hz, 1H), 4.59 (d, J = 12.6 Hz, 1H),
.94 (t, J = 6.1 Hz, 2H), 3.86 (t, J = 9.3 Hz, 1H), 3.00 (t, J = 8.8 Hz, 1H), 2.89 (d, J =
.4 Hz, 1H), 2.51 – 2.11 (m, 8H), 1.78 – 1.65 (m, 3H), 1.63 (d, J = 11.4 Hz, 2H), 1.54
1
3
(
(
s, 3H), 1.41 (d, J = 7.4 Hz, 2H), 1.33 (s, 4H), 1.11 (t, J = 12.7 Hz, 1H). C NMR
100 MHz, CDCl ) δ 169.7(2C), 167.1, 161.3, 145.4, 138.9, 135.2, 130.7, 130.0,
26.7, 120.5, 115.0, 114.7, 81.3, 68.2, 67.0, 63.4, 60.2, 42.9, 36.7, 29.8, 29.1, 29.0,
6.0, 25.9, 25.4, 24.9, 24.9, 24.0, 18.1. HRMS (ESI) calcd for C32 [M+Na]
3
1
2
H
41NNaO
8
+
5
90.2724, found 590.2728.
4
.1.17.3
((1aR,7aS,10aS,10bS,E)-1a-Methyl-8-methylene-9-oxo-1a,2,3,6,7,7a,8,9,10a,10b-dec
ahydrooxireno[2',3':9,10]cyclodeca[1,2-b]furan-5-yl)methyl
(E)-3-(4-((9-(hydroxyamino)-9-oxononyl)oxy)phenyl)acrylate
(20c):
White
1
amorphous solid (yield: 82%). H NMR (400 MHz, CDCl
3
) δ 8.54 (s, 1H), 7.64 (d, J
=
15.9 Hz, 1H), 7.44 (d, J = 8.6 Hz, 2H), 6.88 (d, J = 8.6 Hz, 2H), 6.31 – 6.20 (m, 2H),
.74 (t, J = 8.2 Hz, 1H), 5.56 (d, J = 3.1 Hz, 1H), 4.77 (d, J = 12.5 Hz, 1H), 4.59 (d, J
12.5 Hz, 1H), 3.96 (t, J = 6.4 Hz, 2H), 3.87 (t, J = 9.3 Hz, 1H), 3.05 – 2.95 (m, 1H),
.90 (d, J = 9.4 Hz, 1H), 2.50 – 2.11 (m, 8H), 1.76 (dd, J = 14.1, 6.7 Hz, 2H), 1.69 –
5
=
2
1
13
.59 (m, 3H), 1.56 (s, 3H), 1.43 (s, 2H), 1.32 (s, 6H), 1.13 (t, J = 12.6 Hz, 1H). C
28

NMR (100 MHz, CDCl
3
) δ 169.7(2C), 167.2, 161.3, 145.5, 138.9, 135.2, 130.8, 130.0,
1
2
26.7, 120.6, 115.0, 114.6, 81.2, 68.2, 67.0, 63.5, 60.2, 42.9, 36.7, 33.1, 29.8, 29.3,
9.2, 29.2, 29.1, 26.0, 25.4, 24.8, 24.0, 18.2. HRMS (ESI) calcd for C33
H
43NNaO
8
+
[
M+Na] 604.2881, found 604.2885.
4
.1.18 General procedure for the synthesis of compounds 21a–21c
To a solution of 2 (1.0 mmol), PPh (1.5 mmol) and corresponding acid (1.5
3
mmol) in dry THF (10 mL) were added DIAD (1.5 mmol) under an Ar atmosphere.
The reaction mixture was stirred at room temperature for 8 h. Then, the reaction was
quenched with saturated aqueous NH
combined organic layers were washed with saturated brine, dried over Na
concentrated to give an oily crude product, which was purified on a silica gel column
PE/EA=2:1–1:1 ] to give compound 21a–21c as a white solid.
4
Cl and extracted with EA (3 × 15 mL). The
2
SO , and
4
[
4
.1.18.1
(1aR,7aS,10aS,10bS,E)-1a-Methyl-8-methylene-9-oxo-1a,2,3,6,7,7a,8,9,10a,10b-dec
ahydrooxireno[2',3':9,10]cyclodeca[1,2-b]furan-5-yl)methyl
(
(E)-3-(4-hydroxy-2-methoxyphenyl)acrylate(21a): White amorphous solid (yield: 63%)
1
H NMR (400 MHz, CDCl
3
) δ 7.89 (d, J = 16.1 Hz, 1H), 7.32 (d, J = 8.6 Hz, 1H),
.97 (s, 1H), 6.50 – 6.41 (m, 2H), 6.37 (d, J = 16.1 Hz, 1H), 6.22 (d, J = 3.5 Hz, 1H),
.73 (t, J = 8.2 Hz, 1H), 5.55 (d, J = 3.1 Hz, 1H), 4.74 (d, J = 12.5 Hz, 1H), 4.60 (d, J
6
5
=
=
12.5 Hz, 1H), 3.88 (t, J = 9.3 Hz, 1H), 3.81 (s, 3H), 3.11 – 2.99 (m, 1H), 2.92 (d, J
9.4 Hz, 1H), 2.50 – 2.12 (m, 6H), 1.65 (dd, J = 22.8, 9.8 Hz, 1H), 1.55 (s, 3H), 1.12
29