Synthesis, docking studies and: In vitro evaluation of novel chalcones as potent inhibitors of phosphodiesterase 5 from human platelets and 5A from bovine recombinant

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Page 1 of 37

New Journal of Chemistry

Synthesis, Docking studies and In-vitro evaluation of novel chalcones as potent inhibitors of

Phosphodiesterase 5 from human platelet and 5 A from bovine recombinant

Manish S. Bhatia^a. Amol S. Sherikar^band Rakesh P. Dhavale^a

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DOI: 10.1039/C8NJ02077A

^aDepartment, of Pharmaceutical Chemistry, Bharati Vidyapeeth College of Pharmacy,

Kolhapur, Near

Chitranagri, Kolhapur-416 013 (MS) India.;

^bDepartment, of Pharmaceutical Chemistry, Tatyasaheb Kore College of Pharmacy, Warananagar, Tal-Panhala,

Dist-Kolhapur-416 113 (MS) India.

Email for correnpondence: amol.sherikar@gmail.com

New Journal of Chemistry

Page 2 of 37

Abstract

A series of new nitric oxide donor chalcone moieties were synthesized and evaluate for Phosphodiesterase 5

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(PDE 5) and 5A (PDE 5A) inhibition potential from human plasma and bovine recombinant respectively.

DOI: 10.1039/C8NJ02077A

Molecular docking showed an excellent binding interaction of the synthesised compounds with the receptors.

Synthesis of chalcone intermediate i was carried out by reacting substituted aldehydes and acetophenones on

the basis of Claisen-Schmidt condensation reaction. The nitration reaction was carried out to obtain substituted

cahlcone with phenyl nitrate and nitrate esters as final product. The inhibitory potency of synthesized

compounds was evaluated against PDE 5 from human platelet and PDE5A from bovine recombinant and

compared with Tadanafil and standard inhibitor. The compounds AI7, B5, B7, E7 and E8 containing acetyl,

nitro, carboxy methyl, hydroxyl methyl functionality exhibit a marked inhibitory effect against human platelet

PDE 5. The compounds B2, B4, B5, D4, D6 and E6 containing nitro, fluorine, amino, methyl functionality

produces significant inhibition of recombinant bovin PDE5A. Compound AI7 containing phenyl nitrate moiety

and acetyl functionality on chalcone showed 1.197±3.38 M of inhibitory potency against human platelet

PDE5. Compound B2 containing amide nitrate ester and nitro functionality on chalcone showed 1.241±3.68

M of inhibitory potency against PDE 5A of recombinant bovine. The biocompatibility of synthesized

compounds was checked by in-vitro haemolytic assay. All the tested compounds were observed non-

haemolytic. Compound B2 was tested for in-vitro bacterial reverse mutation test, and found as non-mutagenic.

Key Words Phosphodiesterase, Claisen-Schmidt, Platelet, Bovine, biocompatibility, in-vitro and non-

mutagenic.

Page 3 of 37

New Journal of Chemistry

Introduction

The vascular endothelium plays an important function in the normal regulation of peripheral vasomotor tone in

1

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DOI: 10.1039/C8NJ02077A

conduit and resistance blood vessels. Vascular endothelial cells releases nitric oxide (NO) in response to

hormonal agonists and shear stress. This NO induces vasorelaxation by increasing production of the second

messenger cyclic guanosine monophosphate (cGMP) through activation of soluble guanylate cyclase (sGC) in

vascular smooth muscle.^2-5The binding of NO to the heme moiety leads to formation of an inactive but NO-

responsive 6-coordinate nitrosyl intermediate. This inactive intermediate in the presence of magnesium, cGMP

and pyrophosphate is further converted to a 5-coordinate nitroxyl complex which can be further activated by

NO.^6-7cGMP plays a vital role in various physiologic processes such as ion channel conductance cell growth,

cardiovascular homeostasis, inflammation, apoptosis, cellular mobility and contractility.^6-7Impaired NO

mediated vasodilation in heart failure is partly attributable to hyporesponsiveness of vasorelaxation effector

mechanisms in vascular smooth muscle.^8-10The vasodilatory responses to administration of endothelium

independent cGMP-mediated vasodilatory agents such as nitroglycerin, nitroprusside (soluble guanylate cyclase

activators), atrial and brain natriuretic peptides (particulate guanylate cyclase activators) are decreased in

patients with congestive heart failure when compared with normal subjects.¹¹The examples of nitric oxide

donor compounds reported in literature are nitric oxide-donating pyrazoline derivatives¹², 2-nitrate-1,3-

dibuthoxypropan¹³and nitric oxide releasing NSAIDs like nitric oxide-releasing aspirin, nitro-derivatives of

flurbiprofen^14-15. Cyclic nucleotide phosphodiesterases (PDE) are a superfamily of enzymes responsible for the

hydrolysis of cyclic adenosine 3’,5’-monophosphate (cAMP) and cyclic guanosine 3’,5’-monophosphate

(cGMP).^16-18Currently, the PDE system includes 11 families (PDE1-PDE11) comprising 21 different gene

products.^19-20The cGMP specific PDE 5 is abundant in the penile tissue, platelets, vascular and smooth muscle

tissues due to which this enzyme is the key target for the development of well-known molecules such as

sildenafil (Viagra), vardenafil (Levitra) and tadalafil (Cialis) to treat erectile dysfunction.^21-22NO activates

guanylatecyclase to convert GTP to the second messenger cGMP which, in turn results in smooth muscle

relaxation. cGMP is hydrolysed by PDE 5 to inactive cGMP. PDE 5 inhibitors such as sildenafil thus act to

inhibit cGMP breakdown. Vascular smooth muscle responses to cGMP-dependent vasodilatory stimuli are

regulated by the activity of vascular smooth muscle PDE, which catalyzes hydrolyzation of cGMP to inactive

products.²³Type 5 PDE is the predominant isozyme that contributes to regulation of cGMP content in vascular

smooth muscle.^24-25Chalcones (trans-1,3-diphenyl-2-propen-1-ones) are the biogenetic precursors of all known

flavonoids and are abundantly present in edible plants. Chemically, they consist of open-chain flavonoids in

which the two aromatic rings are joined by a three carbons and , -unsaturated carbonyl system. These

moieties report to have a broad spectrum of biological activities. Chalcones were reported to have fungicidal

activity when joined with agriculture fungicide Strobilurin.²⁶Recently these moieties (chalcones) were reported

to have a PDE 5 and 5A1 inhibitory potential.^27-28Chalcone derivatives of nitric oxide donors were virtually

screened and reported as inhibitors of phosphodiesterase 5A.²⁹

By keeping in view the above discussion, we have synthesized nitric oxide donating chalcone with phenyl

nitrate and nitrate esters moieties. Then the synthesized compounds were screened to evaluate the inhibitory

potency against PDE5 isolated from human platelet and PDE5A from recombinant bovine.

New Journal of Chemistry

Page 4 of 37

Results and discussion

Chemical synthesis

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The schemes 1 and 2 illustrate the synthetic routes used to prepare targeted compounds AI 1-8, Ca 1-8, AII 1-8

DOI: 10.1039/C8NJ02077A

and Cb 1-5. The chalcones were obtained by condensing substituted acetophenone with substituted aldehydes

in presence of 10 % NaOH in ethanol. The obtained chalcones i (Scheme 1 and 2) were then treated with acetic

anhydrite and nitrating mixture in cold condition to obtain final products AI 1-8 and AII 1-8. The chalcone i

was treated with bromoacetyl bromide and dichloromethane in ice bath to obtain the intermediate ii (Scheme 1

and 2). The resulting intermediate was treated with acetonitrile and silver nitrate to obtain the nitrate esters Ca

1-8 and Cb 1-5. All the resulting compounds were obtained in a good yield and purified by recrystalization.

R

1

2

R₁= COCH₃and R₂= CHO

+

R

OH

a

O

i

HO

R

c

b

O

ii

O NO

2

R

O

C

R

AI 1-8

Br

CH

2

d

O

R

C

CH

ONO

2

Ca 1-8

O

Where R is

4- NO₂

AI1

AI2

AI3

AI4

AI5

AI6

AI7

AI8

4-NO₂

Ca1

Ca2

Ca3

Ca5

Ca7

Ca8

3,4- CH₂OH

3,4,5- CH₂OH

4- NCH₃CH₃

4 - CH₃

4 - CH₂CH₃

4-acetyl

3,4 - CH₂OH

3,4,5- CH₂OH

4- Cl

4- F

3- Cl

4-t-butyl

Scheme 1 Synthetic route of target compounds AI 1-8 and Ca 1-8 (a) 10% NaOH, EtOH; (b) HNO₃, acetic

anhydrite, NaHCO₃, ethyl acetate; (c) K₂CO₃, BrCH₂COBr, CH₂Cl₂; (d) AgNO₃; acetonitrile; CH₂Cl₂.

Page 5 of 37

New Journal of Chemistry

R

2

1

R₁= CHO and R ₂= COCH ₃

+

View Article Online

DOI: 10.1039/C8NJ02077A

R

OH

a

O

R

i

HO

b

c

O

ii

R

O

C

CH

Br

2

O NO

2

R

O

AII 1-8

d

O

C

R

ONO₂

CH₂

O

Cb 2-5

Where R is

4- Br

3- NO₂

2,5 - CH₂OH

4- NO₂

4- CH₃

AII1

AII2

AII3

AII4

AII5

AII7

4-CH₂CH₃

2,4- CH₂OH

4- CH₂OH

3,4- Cl

AII8

Cb2

Cb3

Cb4

Cb5

4- CH₂CH₃

3,4-CH₂OH

Scheme 2 Synthetic route of target compounds AII 1-8 and Cb 2-5 (a) 10% NaOH, EtOH; (b) HNO₃, acetic

anhydrite, NaHCO₃, ethyl acetate; (c) K₂CO₃, BrCH₂COBr, CH₂Cl₂; (d) AgNO₃; acetonitrile; CH₂Cl₂

New Journal of Chemistry

Page 6 of 37

R

1

2

R₁= CHO and R₂= COCH₃

+

View Article Online

DOI: 10.1039/C8NJ02077A

R

NH

2

a

O

i

H N

2

R

b

O

ii

Br

NH

CH

C

2

R

c

O

O NO

NH

CH

C

2

R

B 2 -11

Where R is

2- NO₂

2- Cl

4- F

4- NO₂

4- Br

B2

B3

B4

B5

B6

4- COCH₃

4- ter. butyl

4- CH₃

3,4- CH₂OH

3,4,5- CH₂OH

B7

B8

B9

B10

B11

Scheme 3 Synthetic route of target compounds B 2-11 (a) 10% NaOH, EtOH; (b) K₂CO₃, BrCH₂COBr,

CH₂Cl₂; (c) AgNO₃; acetonitrile; CH₂Cl₂.

Page 7 of 37

New Journal of Chemistry

O

Cl

OHC

C

R

= OH or NH

View Article Online

DOI: 10.1039/C8NJ02077A

2

+

R

1

R

2

a

O

CHO

R

2

i

R

1

d

b

O

OH

NH

2

O

R

ii

iii

R

1

c

e

O

ONO

N

H

C

CH

Br

2

O

R

O

iv

R

1

f

D1 - 9

O

N

C

CH

ONO

2

H

O

R

O

R

1

E 1 -10

R1

R2

R

R1 R2

R

F

Br

Cl

OH 4- CH₂CH₃

OH 4- CH₃

NO₂NH₂4- CH₂OH

D1

D2

D3

D4

D5

D6

D7

D8

D9

E1

E2

E3

E4

E5

E6

E7

E8

E9

E10

F

NH₂4- Br

NH₂4- Cl

NH₂4- Br

NH₂4-NO₂

NH₂3- Br

NH₂4- CH₂OH

NH₂3- Br

CH₃OH 4- NO₂

CH₃OH 4- NH₂

CH₃OH 3- NO₂

CH₃OH 3,4- CH₂OH

CH₃OH 4- Cl

Br

Cl

CH₃OH 4- CH₂CH₃

NO₂NH2 4- CH₂CH₃

NH₂3,5- CH₂OH

Scheme 4 Synthetic route of target compounds D 1-9 and E 1-10 (a) AlCl₃, HCl; (b) and (d) Substituted

acetophenone, 10% NaOH, EtOH; (c) HNO₃, acetic anhydrite, NaHCO₃, ethyl acetate; (e) K₂CO₃,

BrCH₂COBr, CH₂Cl₂; (f) AgNO₃; acetonitrile; CH₂Cl₂.

New Journal of Chemistry

Page 8 of 37

The scheme 3 explains the synthetic route to prepare targeted compounds B 2-11. All the procedures are similar

as described in scheme 1 and 2. The scheme 4 explains the synthetic route used for preparing D 1-9 and E 1-

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11. The intermediate i was prepared by Friedel Crafts reaction by reacting acid chloride with substituted

DOI: 10.1039/C8NJ02077A

aldehydes then treated with substituted ketones to obtain ii and iii intermediates. The targeted compounds D 1-9

and E 1-10 were synthesized by same procedure as described in scheme 1 and 2.

The IR spectra of prepared chalcones showed (C=O) stretching at 1600 to 1700 cm^-1due to formation of

1

carbonyl bond in chalcones. H NMR spectra recorded for the prepared compounds in CDCl₃clearly support

the proposed structures. The protons of chalcone ring system in all the synthesized compounds were showed

prominent peaks from  7.00 to 7.90 with singlet, doublet, triplet and multiplets. The aliphatic protons were

1

13

also confirmed from H NMR. From the result of C NMR it can be concluded that the synthesis of final

targeted compounds was achieved successfully. Mass spectra and elemental analysis are in agreement with

proposed structures of the prepared compounds.

Biological evaluation of inhibitory potency

Compounds AI 1-8, AII 1-8, Ca 1-8, Cb 1-5, B 2-11, D 1-9 and E 1-11 were evaluated for inhibition of human

platelet PDE 5 and recombinant bovin PDE 5A. The synthesized compounds inhibit PDE 5/PDE 5A in a

concentration dependent manner. Tested compounds showed statistical significances with P˂0.01, 0.05 and

0.25 compared with IC₅₀values of standard (inhibitor). As observed in table 1, derivatives AI7, D5, B5, E6, E7

and E8 exhibit a marked inhibitory effect on PDE5 obtained from human platelet. Out of these compounds AI7

and B5 exhibit maximum inhibitory potency, their IC₅₀were found to be 1.197±3.38 and 1.425±0.09 M

respectively. The standard inhibitor and Tadalafil showed 1.690±3.47 and 1.616±2.37 M of inhibition of PDE

5 respectively. The study also indicates that the compounds D5, E6, E7 and E8 showed 1.625±2.08,

1.817±2.38, 1.663±2.96 and 1.961±3.57 M IC₅₀values respectively, indicating these compounds are also

potent inhibitors of PDE 5.

Table 1 IC₅₀concentrations of synthesized compounds and standards against PDE5 and PDE5A from Human

Plasma and Recombinant Bovine respectively.

Comp

Code

Human

Bovine

Comp

Human

Bovine

Comp

Code

Human

Bovine

Platelet

Recombinant Code

Platelet PDE5 Recombinant

PDE5 (M)

PDE5A (M)

(M)

PDE5A (M)

(M)

PDE5A (M)

5.695±3.10^a

6.812±0.30^a

4.391±3.22^a

3.692±0.29^a

8.692±2.67^a

9.885±0.32^a

1.197±3.38^a

3.736±3.79^b

5.241±3.26^a

2.886±2.47^a

2.339±3.21^a

2.359±4.21^a

5.838±3.35^a

1.910±0.31^a

5.926±6.45^a

9.158±2.63^a

3.111±2.83^a

2.713±2.44^a

4.748±2.03^a

7.692±2.23

2.436±3.45

9.761±0.31^ns

5.907±1.34^a

8.174±3.15^c

6.803±3.06^b

9.913±2.57^a

6.750±3.08^a

5.379±2.37^a

1.425±0.09^a

9.866±2.48^a

1.993±3.10

3.373±2.79

4.347±2.28^a

9.143±2.57^a

2.338±3.28^a

5.353±2.99^a

1.241±3.68^a

2.044±0.30^a

1.322±2.78^a

7.808±1.94^a

3.923±2.68^a

3.771±8.93^a

1.625±2.08^a

7.733±3.39^a

8.305±1.77^b

2.764±0.09^a

2.500±3.58^b

3.705±2.16^a

4.019±3.18^b

7.765±2.93^a

2.620±1.75^a

3.579±1.99^a

7.066±2.78^b

9.367±2.90^a

1.745±2.73^a

2.241±3.84^a

9.882±2.67^c

7.350±3.83^c

1.996±2.65^a

2.950±2.18^a

5.593±1.86^a

6.083±2.64^a

4.273±2.01

AI1

AI2

AI3

AI4

AI5

AI6

AI7

AI8

AII1

AII2

AII3

Ca7

D4

D5

D6

D7

D8

D9

E1

E2

E3

E4

E5

Ca8

Cb2

Cb3

Cb4

Cb5

B2

B3

4.751±0.27^a

5.043±2.60^a

7.220±0.12^b

B4

B5

B6

Page 9 of 37

New Journal of Chemistry

4.550±0.33^a

9.791±1.70^c

9.063±0.32^a

9.280±2.12^a

4.815±2.98^a

2.824±0.18^a

3.865±3.36^b

4.632±0.34^c

1.339±3.01^a

1.356±3.02^a

3.015±0.13^a

4.672±2.56^b

7.543±0.28^a

7.984±3.02^a

6.217±0.31^a

2.144±2.21^a

3.404±3.08^a

2.782±2.07^a

4.360±1.87^a

8.834±0.19^a

5.675±2.07^b

4.203±9.84^a

5.447±2.93^a

3.546±2.96^a

4.057±2.08^a

1.817±2.38^a

1.663±2.96^a

1.961±3.57^b

1.356±1.05^a

6.511±3.12^a

AII4

AII5

AII7

AII8

Ca1

Ca2

Ca3

Ca5

B7

E6

5.222±0.06

8.815±3.66^ns

5.065±1.96^a

9.620±2.06^c

4.825±0.11^a

5.580±1.36^b

2.655±3.15^a

B8

E7

6.099±0.34^c

B9

E8

View Article Online

a

DOI: 10.1039/C8NJ02077A

7.375±2.78

6.163±0.04

B10

B11

D1

D2

D3

E9

2.314±3.07^a

1.616±2.37^a

1.690±3.47

6.084±2.69a

5.317±0.43^a

1.159±4.98^a

1.195±2.22

2.336±4.24^a

E10

Tadal.

Inhib.

Cont.

Tadal. = Tadalafil

Inhib. = Standard Inhibitor, was 3- isobutyl-1-methylxanthine (IBMX) given with assay kit.

Cont. = Control

IC₅₀values reported as Conc. ± SEM; SEM of three independent experiments performed in duplicate.

a (95 % confidence interval) p = ˂ 0.01, b (90 % confidence interval) p = ˂ 0.05, c (75 % confidence interval) p = ˂ 0.25, ns = non

significant.All the procedures were performed as per the instructions given in assay manual.

The compounds AI3, AII4, AII5, Ca7, B2, B4, D6, E1 and E6 produces significant inhibition of recombinant

bovin PDE 5A. The compound AII5, B2, B4 and E6 showed IC₅₀values 1.356±3.02, 1.241±3.68, 1.322±2.78

and 1.356±1.05 M respectively. The standard inhibitor and Tadalafil showed IC₅₀values 1.195±2.22 and

1.159±4.98 M respectively. The comparison of inhibitory potency of some potent compounds against PDE

and PDE5A with standard and Tadalafil is showed in figure 1.

Figure 1 Showing PDE 5 and PDE 5A inhibitory potency of synthesized compounds with Tadalafil and

standard inhibitor.

The structure activity relationship data reveals that the inhibitory potency against PDE 5 depends strongly on

nature of substitution on R in scheme 1, 2 and 3 as well as R and R1 in scheme 4. In scheme 1, different

substitutions were carried out as shown in series AI 1-8 and Ca1-8. In series AI 1-8 substitution of acetyl group

at para position (AI7) produce inhibitory potency of 1.197±3.38 M IC₅₀against PDE 5 from human platelet,

which is more than that of standard inhibitor and Tadalafil. Substitution of methyl, methoxy, ethyl butyl and

nitro at R decreases inhibitory potency against PDE 5. The same series (AI 1-8) was evaluated against PDE 5A

New Journal of Chemistry

Page 10 of 37

from recombinant bovin which produce interesting and different results. Compound AI3 with methoxy

substitution at 3, 4 and 5 position produce maximum inhibitory potency of about 1.910±0.31 M IC₅₀against

View Article Online

PDE 5A, which is less than that of standard inhibitor and Tadalafil. Compound AI7 with _Da_Oc_Ie_{: 1}t₀y_.1l₀s₃₉u_/b_C8s_Nti_Jt₀u₂t₀i₇o_7An at

para position was not found to be more potent against PDE 5. All other substitutions in this series (AI 1-8) was

found to be less potent against PDE 5A than AI3. The basic mechanism for this diversity in inhibitory potency

may be the difference of gene product present in PDE 5 form human platelet and PDE 5A from recombinant

bovin. The second series in scheme 1 includes compounds Ca 1-8 with variety of substitution on R. Compound

with chlorine substitution at meta position (Ca8) produce inhibitory potency of about 2.436±3.45 M IC₅₀

against PDE 5 from human platelet and it was found to be less potent than AI7. This explains the importance of

phenyl nitrate and nitrate ester moieties for inhibitory potency against PDE 5. The substitutions like nitro,

methoxy, fluorine leads to less potency against PDE 5. Structure Ca7 with fluorine at para position showed

inhibitory potency of 1.993±3.10 M IC₅₀against PDE 5A which is equal to that of AI3. Both structures (AI3

and Ca7) were found to have less potent than standard inhibitor and Tadalafil against PDE 5A. This difference

in inhibitory potency towards PDE 5 from human platelet and PDE 5A from recombinant bovin may be the

different gene product present in both enzymes.

The scheme 2 includes two series of compounds i.e. AII 1-8 and Cb 2-5 with variety of substitutions. In first

series (AII 1-8) compound with 2, 4 methoxy (AII3) substitution produce 2.339±3.21 M IC₅₀against PDE 5

which was highest amongst same series but lower as compared to AI7, standard inhibitor and Tadalafil. The

other substitutions like bromine, nitro, methoxy and methyl reduces the inhibition. Molecules with nitro (AII4)

and methyl (AII5) substitution at para position showed inhibitory potency of about 1.339±3.01 and 1.356±3.02

M IC₅₀respectively against PDE 5A. This inhibitory potency was found to be more than that of AI3 but less

than that of standard inhibitor and Tadalafil. This highlights the importance of carbonyl functionality and

position of double bond between two adjacent carbons in chalcones. The other substitutions like bromine, nitro

and ethyl were found to produce lesser potency against PDE 5A. In second series (Cb 2-5) all the molecules

were found to be less active as they showed lower inhibitory potency against PDE 5 and 5A except Cb4 with 3,

4 chlorine substitution with IC₅₀2.338±3.28 M against PDE 5A. The above results clearly indicate that the

phenyl nitrate moiety plays an important role than nitrate ester for inhibition of PDE 5 and 5A. The presence of

carbonyl functionality towards phenyl nitrate produces more potent action. The position of double bond

between adjacent carbons should be away from phenyl nitrate for maximum potency.

The scheme 3 depicts a series of molecules with amide linkages between benzene ring and nitrate moiety. It

includes series of molecules (B 2-11) with variety of substitutions. Out of these, the compound containing para

nitro substitution (B5) showed maximum inhibitory potency against PDE 5 which was found to be 1.425±0.09

M IC₅₀. This molecule was found to be more potent inhibitor of PDE 5 than standard inhibitor and Tadalafil

but it is somewhat less potent than AI7. The other substitutions like chlorine, fluorine, bromine, tertiary butyl,

methyl, methoxy and carboxymethyl were found to produce lower inhibitory potency against PDE 5. The

molecules with nitro substitution at ortho position (B2) and fluorine at para position (B4) showed inhibitory

potency of about 1.241±3.68 and 1.322±2.78 M IC₅₀respectively against PDE 5A. This inhibitory potency

Page 11 of 37

New Journal of Chemistry

was observed to be more than that of AII4 and AII5 but less than that of standard inhibitor and Tadalafil. The

substitutions like bromine, tertiary butyl, methyl, methoxy and carboxymethyl leads to decrease in inhibitory

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potency. From above results it can be concluded that the amide linkage also leads to a potent PDE 5 and 5A

DOI: 10.1039/C8NJ02077A

inhibitor.

Series D 1-9 and E 1-10 were reported in scheme 4 with variety of substitutions at R1 and R positions. In series

D 1-9 OH is present at R2 position which gives phenyl nitrate moiety and in E 1-10 NH₂is present at R2

position which leads to amide linked nitrate moiety. The compound D5 with methyl at R1 and amide at para

position (R) produce maximum inhibitory potency of about 1.625±2.08 M IC₅₀against PDE 5 from human

platelet which is equal to inhibitory potency produced by standard inhibitor and Tadalafil but lesser than that of

AI7 and B5. Other substitutions like fluorine, bromine and chlorine on R1 leads to decrease in inhibitory

potency against PDE 5. Substitutions like ethyl, methyl, nitro, methoxy and chlorine at R decreases the

inhibitory potency against PDE 5. The molecule (D6) with methyl at R1 and nitro at R showed 1.745±2.73 M

IC₅₀against PDE 5A from recombinant bovin, which is less than that of B2, standard inhibitor and Tadalafil.

The other molecules in this series with variety of substitutions like fluorine, bromine, chlorine at R1 and ethyl,

methyl, methoxy and chlorine at R in this series leads to decrease in inhibitory potency against PDE 5A. In

second series (E 1-10), the compound (E6) with bromine at both R1 and R showed 1.663±2.96 M IC₅₀against

PDE 5 which is equal to standard inhibitor, Tadalafil and D5 but less than that of AI7 and B5. The compound

(E7) with bromine at R1 and nitro at R produce 1.356±1.05 M IC₅₀against PDE 5A, which is more than D6

but less than that of B2, standard inhibitor and Tadalafil. The different substitutions like nitro, fluorine, chlorine

at R1 and ethyl, methoxy, chlorine at R in this series leads to decrease in inhibitory potency. From above

observations we can conclude that the phenyl nitrate moiety is crucial for inhibition of PDE 5 and amide linked

nitrate on chalcones for inhibition of PDE 5A.

Compound AI7, with acetyl substitution at R appears to be the most potent PDE5 inhibitor. It is phenyl nitrate

containing chalcone molecule. The comparison of PDE 5 inhibitory potency of AI7 and other active molecules

with standard inhibitor and Tadalafil is given in figure 1. It showed that AI7 is more potent inhibitor of PDE 5

than standard inhibitor and Tadalafil. The side chain length and substitutions also have affect on inhibitory

potency. The side chain with carbonyl group and methyl spacer between phenyl ring and organic nitrates was

found to be essential requirement for inhibitory potency. The side chain with amide linkage was found to be

more potent inhibitor than esters. The basic chalcone backbone was observed to be very important for

inhibitory action against PDE 5 and 5A. The substitutions on aromatic ring of chalcone, the position of double

bonds in chalcone moiety and the position of C=O seems as a modulator for activity and relative potency

against PDE 5 and 5A. The comparison of inhibitory potency of B2 and other active molecules against PDE 5

and 5A with standard inhibitor (IBMX) and tadalafil is showed in figure 1 which reveals that the B2 is having

inhibitory potency more than 90% against PDE 5A as compared to standard inhibitor (IBMX) and tadalafil. The

structure of B2 reveals the structural requirement for potency against PDE, which includes a chalcone moiety

with amide linkage separated from organic nitrate by carbonyl and methyl group, also there is presence of NO

group at ortho position on phenyl ring which is electron withdrawing. It also highlights the potential of this

approach of evaluating nitric oxide donating molecules with chalcone as a basic skeleton for inhibition of PDE.

New Journal of Chemistry

Page 12 of 37

The probable mechanism by which these molecules inhibit PDE includes inactivation or degradation of active

site of enzyme by binding to catalytic domain. This form of inactive or degraded PDE will not cause hydrolyses

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of cAMP and/or cGMP, leading to the formation of the active 5ʹ-cAMP and 5ʹ-cGMP, respectively which

DOI: 10.1039/C8NJ02077A

influences the cellular response of biological system.

In-vitro toxicity assessment of synthesized compounds

Haemolytic assay

The haemolytic assay is used to test if a chemical (under evaluation) is toxic to circulating RBCs. Peripheral

blood is centrifuged to sediment RBCs. The chemical under evaluation is added and incubated to permit

reaction between the chemical and RBCs. The optical density readings are taken to measure the amount of

haemolysis taken place. The degree of haemolysis is directly proportional to cytotoxicity to the RBCs.

None of concentrations of the tested compounds were haemolytic. Based on these results, the thus synthesized

compounds were found to be non-haemolytic. The representative result of compounds having potency against

PDE is presented in table 2.

Table 2 Showing result of haemolytic test

Com.

Code

% Haemolysis Observed

0.1 10

mM mM mM mM

1

5

B2

B4

E1

E6

E7

00

0.01

00

0.74

0.21

0.11

Positive Control = 100, Negative Control = 00, Vehicle Control = 2.1

Triton X-100 was used as positive control and untreated RBC with PBS served as negative control. The

percentage of haemolysis under each concentration (0.1 mM, 1 mM, 5 mM and 10 mM) of test compound

employed is tabulated.

Bacterial reverse mutation test

AMES (Bacterial reverse mutation test) is used to assess the mutagenicity of any compound or drug using

histidine dependent bacterium. If the compound has ability to cause mutation then the bacterium will show

reverse reaction in its histidine-based synthesis.

Ames test was done to study the mutagenic potential of compounds (B2) in Salmonella typhimurium strains TA

98 and TA 100 without metabolic activation system. Four concentrations (0.1 mM, 1 mM, 5 mM and 10 mM)

of compounds were incubated with Salmonella typhimurium strains did not form any colonies whereas sodium

azide treated strains formed revertant colonies. The colonies were counted, the values were also statistically

significant between compounds treated and sodium azide treated groups (Table 3).

Page 13 of 37

New Journal of Chemistry

Table 3 Bacterial reverse mutation test inhibitory effect of B2 on Salmonella typhimurium TA100 without

metabolic activation system

View Article Online

DOI: 10.1039/C8NJ02077A

Sr.

No.

1.

Compound Name

and Concentration

Untreated

S. typhimurium

(TA100)

256

2.

0.1 mM

321

3.

1 mM

342

4.

5 mM

359

5.

10 mM

324

6.

Sodium azide

1,530

Molecular docking results

The molecular docking has been carried out by two modes, the first one include docking with oxygen in PDB

and second is docking without oxygen in PDB. Molecular docking with oxygen showed an excellent binding

interaction of the synthesized compounds with the receptor 1XOZ with B2 showing the docking score –72.50

kcal/mol. The molecular docking for compound B2 with receptor 1XOZ is shown in figure 2 (a & b) which

indicates that amide linked nitrate moiety of compound B2 bound to aromatic site forms hydrogen bond

interactions with ASP 764A. The nitro group of phenyl ring forms hydrogen bond interaction with LEU 725A.

The phenyl ring forms hydrophobic interactions with LEU 627A and ILE 778A. The amide linked nitrate

produces hydrophobic interactions with SER 766A, ALA 767A and ILE 778A. The oxygen, nitrate and carbon

linked with amide linkage and aromatic ring formed Van der Walls interactions with the catalytic PHE 786A,

CIA 326A, VAL 782A, TYR 612A, HIS 617A. As supported by the enzymatic activity assays, all these

interactions are crucial factors contributing to inhibitory potency. There are 11 amino acid residues (Figure 2 (a

& b)) found in the active binding site of 1XOZ complex namely: ASP 764A, LEU627A, ILE 778A, LEU 725A,

SER 766A, ALA 767A, PHE 786A, CIA 326A, VAL 782A, TYR 612A, HIS 617A.

The docking of B2 into 1XOZ without oxygen produces docking score of -67.34 kcal/mol, it shown in figure 3

(a & b). The phenyl nitro group forms hydrogen bonding with LEU 725A. The amide nitrogen forms nitrogen

bonding with ASP 764 A. The nitrate molecule forms hydrophobic interactions with SER 766A, ALA 767A,

ILE 778A, VAL 782A and LEU 627A. The remaining part of the molecule forms Van der Walls interactions

with PHE 786A, LEU 725A, CIA 326A, TYR 612A and HIS 617A. The binding pattern and docking score

observed to be differing than that of PDB containing oxygen. The PDB containing oxygen produces more

prominent docking interactions and scores than that of PDB without oxygen.

New Journal of Chemistry

Page 14 of 37

View Article Online

DOI: 10.1039/C8NJ02077A

(a)

(b)

Figure 2. a. Binding interactions of the amino acid residues of the protein – 1XOZ containing oxygen

complexity, with compound B2 and b showing van der Walls interaction of the protein – 1XOZ containing

oxygen complexity, with compound B2.

(Light Blue colour indicates hydrophobic interaction, Green colour indicates hydrogen bonding and pink

colour indicates Van der Walls interactions)

Page 15 of 37

New Journal of Chemistry

View Article Online

DOI: 10.1039/C8NJ02077A

(a)

(b)

Figure 3. a. Binding interactions of the amino acid residues of the protein – 1XOZ without oxygen complexity,

with compound B2 and b showing van der Walls interaction of the protein – 1XOZ without oxygen complexity,

with compound B2.

(Light Blue colour indicates hydrophobic interaction, Green colour indicates hydrogen bonding and pink

colour indicates Van der Walls interactions)

New Journal of Chemistry

Page 16 of 37

The above docking model was compared with binding model of compounds 8 (A), 9 (B), and 20 (C) with PDE

5 reported by Guang-Fu Yang et al.³⁰In this paper the reported compounds 8 (A), 9 (B), and 20 (C) binds with

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PDE 5 with hydrogen bond interaction between the nitrogen of the amine group of the Glu817 side chain and

DOI: 10.1039/C8NJ02077A

the carbonyl oxygen of the ligands. This hydrogen bond exists in all of the docked PDE 5-ligand binding

structures. In our docking model of B2 with PDE 5 there exist a hydrogen bond interaction between amide

linked nitrate moiety of compound B2 bound to aromatic site with ASP 764A and between nitro group of

phenyl ring with LEU 725A. Our binding model of B2 also reveals hydrophobic interaction between phenyl

ring with LEU 627A, ILE 778A and amide linked nitrate with SER 766A, ALA 767A and ILE 778A

respectively. The Van der Walls interactions was observed between oxygen, nitrate, carbon linked with amide

linkage and the catalytic site of 1XOZ containing PHE 786A, CIA 326A, VAL 782A, TYR 612A, HIS 617A.

Conclusions

The nitric oxide donor compounds with chalcone as a basic skeleton had promising PDE 5 and 5A inhibitory

potential. Compounds having substitutions like methoxy, hydroxyl, acetyl, nitro and ethoxy showed better PDE

inhibition potential. Compounds having bromo and fluoro substituents have exhibit more PDE 5A inhibition

potential. Our results suggest that these structures represent interesting lead compounds for the development of

novel molecules for PDE 5 and 5A inhibition. The biocompatibility of these compounds was tested by in-vitro

haemolytic and AMES test, All the end points consistently demonstrated the lack of toxicity and mutagenicity

in the concentrations tested. These tests are considered gold standards of in-vitro assessment. This outcome

may be worth further investigations to understand whether such compounds have real potential to enhance

vascular muscle relaxation in clinical trials. A step forward will consist in investigating whether such

compounds may prevent some cardiovascular complications and can be used for pain management concurrently

with vascular pathophysiologies.

Experimental

Materials

Melting points were determined by open capillary method and values given were uncorrected. IR spectra were

1

recorded on BRUKER ALPHA – 100508. The H NMR and ¹³C spectra were taken on 300 and 125 MHz

Varian NMR instrument (Bruker) in CDCl₃with hexamethyldisiloxane (HMDS) as an internal standard.

Chemical shifts were reported in  values (ppm) relative to internal HMDS. The abbreviation s = singlet, d =

doublet, t = triplet, q = quadruplet, m = multiplet, ArH = aromatic CH were used throughout. The M/Z was

determined on GC-MS (Shimadzu). Gas chromatography interfaced to a Mass spectrometer (GC-MS- 2010)

equipped with a Elite-1 fused silica capillary column (RTZ i 5ms 30 mm x 0.25 mm 1D). Helium gas

(99.999%) was used as the carrier gas at constant flow rate of 1 ml / min and an injection volume of 2 µl was

employed (Split ratio of 50:50); Injector temperature 250° C; ion-source temperature 250° C. Elemental

analyses (C, H and N) were realized on a Carlo-Erba EA 1108-elemental analyser and compared with

theoretical values. All reactions were routinely checked by TLC on silica gel G.

Chemical synthesis

General Procedure for synthesis of compound i of scheme 1, 2 and 3.

Page 17 of 37

New Journal of Chemistry

Compound i was obtained by dissolving a specific amount of aromatic aldehyde (0.01 mol) and acetophenone

(0.01 mol) in 10 ml of 95% ethanol in a flask with magnetic stirrer. 10% NaOH in ethanol was added in

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reaction mixture. The whole assembly was kept in ice bath with magnetic stirrer for 10 - 15 min, while the

DOI: 10.1039/C8NJ02077A

precipitation observed. Reaction mixture was added to 50% dilute acetic acid.³¹Then the respective products

were purified by recrystallization. The purity of the compounds was determined by TLC using several solvent

systems of different polarity.

General Procedure for synthesis of compounds AI1-8 of scheme 1.

To acetic anhydride (3 ml) was added gradually, with stirring, 70% nitric acid (0.26 ml), while keeping the

temperature between 20-30⁰C by external cooling. With continuous vigorous stirring the mixture was cooled to

5-10⁰C and weighed amount of compound (i) was added. After 10 min the reaction mixture was stirred at 10-

15⁰C. The resulting reaction mixture was poured into ice-water, stirred for 1 h. then NaHCO₃was added by

portion until CO₂evolution ceased. The water solution was extracted with 3×20 ml of ethyl acetate. Combined

extracts were dried and concentrated and recrystallized from ethanol.

(E)-4-[3-(3-nitrophenyl)prop-2-enoyl]phenyl nitrate (AI1)

By following above methods, the title compound AI1 was obtained as a pale yellow solid in 68.72 % yields; mp

90–92 ⁰C; IR (KBr): 760, 1060 (C-N aromatic), 1681 (C-O chalcone), 1714 (aromatic) cm^-1; ¹H NMR (CDCl₃)

: 7.38 (dt, 2H, J = 7.50 Hz), 7.63 (s, 1H), 7.69 (m, 1H), 7.94 (m, 1H), 7.97 (m, 2H, J = 7.50 Hz), 8.39 (dt, 2H)

13

8.57 (m, 1H, J = 7.50 Hz); C NMR (CDCl₃) : 122.1 (CH, C-16), 123.5 (CH=CH, C-9), 124.7 (CH, C-13),

128.9 (CH, C-2), 128.9 (CH, C-3), 129.6 (CH, C-4), 129.6 (CH, C-5), 129.8 (CH. C-14), 133.8 (C, C-1), 134.2

(CH, C-12), 137.7 (C, C-11), 141.6 (CH=, C-10), 143.3 (C-N, C-6), 147.7 (C-N, C-15), 191.7 (C=O, C-8); MS

(m/z) 315.0 [M]⁺; Anal Calcd for C₁₅H₁₀N₂O₆: C, 56.26; H, 3.15; N, 7.29 found C, 56.10; H, 3.10; N, 7.18.

(E)-4-{3-[3,4-bis(hydroxymethyl)phenyl]prop-2-enoyl}phenyl nitrate (AI2)

By following above methods, the title compound AI2 was obtained as a pale yellow solid in pale yellow solid

in 75.09 % yield; mp 110-112 ⁰C; IR (KBr) 1064 (C-N aromatic), 1681 (C-O chalcone), 1700 (aromatic), 2952

cm^–1; ¹H NMR (CDCl₃) : 2.30 (s, 3H), 4.80 (d, 4H), 7.38 (m, 3H, J = 15.10 Hz), 7.50 (d, 2H), 7.71 (dt, 1H, J =

13

15.10 Hz), 7.97 (m, 2H, J = 7.50 Hz); C NMR (CDCl_3,) : 21.4 (CH₃, C-7), 62.6 (CH₂, C-20), 62.8 (CH₂, C-

18), 123.5 (CH, C-9), 127.4 (CH, C-13), 127.9 (CH, C-12), 128.9 (CH, C-2), 128.9 (CH, C-3), 129.3 (CH, C-

14), 129.6 (CH, C-4), 129.6 (CH, C-5), 132.9 (C, C-11), 133.8 (C, C-1), 138.5 (C, C-15), 143.3 (C-N, C-6),

144.0 (CH=, C-10), 191.7 (C=O, C-8); MS (m/z) 330.0 [M]⁺; Anal Calcd for C₁₇H₁₅NO₆: C, 62.82; H, 4.74; N,

7.33 found C, 62.76; H, 4.88; N, 7.30.

(E)-4-{3-[3,4,5-tris(hydroxymethyl)phenyl]prop-2-enoyl}phenyl nitrate (AI3)

By following above methods, the title compound AI3 was obtained as a yellow solid in 74.91 % yield; mp 122-

0

1

124 C; IR (KBr) 842, 1060 (C-N aromatic), 1681 (C-O chalcone), 1702 (aromatic), 3312 cm^–1. H NMR

(CDCl₃) : 2.30 (s, 3H), 4.80 (s, 6H, J =4.5 Hz ), 7.38(m, 3H, J = 15.10 Hz), 7.53 (s, 2H), 7.72 (dt, 1H, J =

15.10 Hz, =CH), 7.97 (m, 2H, J = 7.50 Hz); ¹³C NMR (CDCl₃) : 21.4 (CH₃, C-7), 59.1 (CH₂, C-20), 63.3

(CH₂, C-18), 122.2 (CH, C-9), 128.3 (CH, C-12), 128.3 (CH, C-13), 128.9 (CH, C-2), 128.9 (CH, C-3), 129.6

(CH, C-4), 129.6 (CH, C-5), 132.3 (C, C-11), 133.8 (C, C-1), 138.4 (C, C-16), 139.8 (C, C-14), 139.8 (C, C-

New Journal of Chemistry

Page 18 of 37

15), 143.3 (C-N, C-6), 143.7 (CH=, C-10), 185.6 (C=O, C-8); MS (m/z) 360.1 [M]⁺; Anal Cacld for

C₁₈H₁₇NO₇: C, 65.39; H, 4.66; N, 3.84 found C, 65.31; H, 4.54; N, 3.80.

View Article Online

DOI: 10.1039/C8NJ02077A

(E)-4-{3-[4-(dimethylamino)phenyl]prop-2-enoyl}phenyl nitrate (AI4)

By following above methods, the title compound AI4 was obtained as a pale yellow solid in 70.36 % yield; mp

0

1

110-112 C; IR (KBr) 1063 (C-N aromatic), 1681 (C-O chalcone), 1710 (aromatic), 2740 cm^–1; H NMR

(CDCl₃) : 2.30 (s, 3H), 2.90 (s, 6H), 6.54 (dt, 1H), 6.88 (dd, 1H, J = 7.50 Hz ), 7.17 (t, 1H), 7.38 (m, 2H, J =

15.10 Hz), 7.72 (m, 1H, J = 7.50 Hz), 7.97 (m, 2H, J = 7.50 Hz- ArH); ¹³C NMR (CDCl₃) : 21.4 (CH₃, C-7),

40.8 (CH₃, C-19), 40.8 (CH₃, C-20), 112.5 (CH, C-13), 115.8 (CH, C-16), 122.0 (CH, C-12), 123.5 (CH, C-9),

128.9 (CH, C-2), 129.2 (CH, C-14), 129.6 (CH, C-4), 129.6 (CH, C-5), 133.8 (C, C-1), 133.8 (C, C-11), 143.3

(C-N, C-6), 144.0 (CH=, C-10), 151.4 (C-N, C-15), 185.4 (C=O. C-8); MS (m/z) 313.1 [M]⁺; Anal Cacld for

C₁₇H₁₇N₂O₄: C, 66.83; H, 5.35; N, 3.54 found C, 66.81; H, 5.22; N, 3.57.

(E)-4-[3-(4-methylphenyl)prop-2-enoyl]phenyl nitrate (AI5)

By following above methods, the title compound AI5 was obtained as a yellowish white solid in 68.71% yield;

0

1

mp 94-96 C; IR (KBr) 1078 (C-N aromatic), 1681 (C-O chalcone), 1710 (aromatic), 2940 cm^–1; H NMR

(CDCl₃) : 2.30 (s, 3H), 7.20 (t, 1H, J = 7.50 Hz), 7.38 (m, 3H, J = 15.10 Hz), 7.27 (m, 1H, J = 7.50 Hz), 7.33

(tt, 1H), 7.43 (m, 1H, J = 7.50 Hz), 7.73 (m, 1H, J = 15.10 Hz), 7.97 (m, 2H, J = 7.50 Hz); ¹³C NMR (CDCl₃) :

21.3 (CH₃, C-18), 21.4 (CH₃, C-7), 123.5 (CH, C-9), 124.0 (CH, C-12), 128.9 (CH, C-2), 128.9 (CH, C-3),

129.5 (CH, C-14), 129.5 (CH, C-16), 129.6 (CH, C-4), 129.6 (CH, C-5), 129.7 (CH, C-13), 133.8 (C, C-1),

135.9 (C, C-11), 138.9 (C, C-15), 143.3 (C-N, C-6), 144.0 (CH=, C-10), 191.7 (C=O, C-8); MS (m/z) 284.0

[M]⁺; Anal Calcd for C₁₆H₁₃NO₄: C, 63.53; H, 5.45; N, 3.84 found C, 63.71; H, 5.37; N, 3.74.

(E)-4-[3-(4-ethylphenyl)prop-2-enoyl]phenyl nitrate (AI6)

By following above methods, the title compound AI6 was obtained as a pale yellow solid in 77.00 % yield; mp

108-110 ⁰C; IR (KBr) 986, 1063 (C-N aromatic), 1671 (C-O chalcone), 1700, 2940 cm^–1; ¹H NMR (CDCl₃) :

1.27 (t, 3H, J = 12.50 Hz), 2.28 (m, 2H), 7.24 (m, 1H, J = 7.50 Hz) 7.35 (t, 1H, J = 7.50 Hz), 7.37 (m, 1H), 7.38

13

(m, 3H, J = 7.50 Hz), 7.43(m, 1H, J = 7.50 Hz), 7.73 (dt, 1H, J = 15.10 Hz), 7.97 (m, 2H, J = 7.50 Hz); C

NMR (CDCl₃) : 15.1 (CH₃, C-19), 28.5 (CH₂, C-18), 123.5 (CH. C-9), 124.8 (CH, C-12), 127.4 (CH, C-16),

128.3 (CH, C-14), 128.9 (CH, C-2), 128.9 (CH, C-3), 129.2 (CH, C-13), 129.6 (CH, C-4), 129.6 (CH, C-5),

133.3 (C, C-11), 133.8 (C, C-1), 143.3 (C-N, C-6), 143.5 (C, C-15), 144.0 (CH, C-10), 191.7 (C=O, C-8); MS

(m/z) 298.1 [M]⁺; Anal Calcd for C₁₇H₁₅NO₄: C, 64.00; H, 5.15; N, 3.72 found C, 64.11; H, 4.94; N, 3.54.

(E)-4-[3-(4-acetylphenyl)prop-2-enoyl]phenyl nitrate (AI7)

By following above methods, the title compound AI7 was obtained as a yellowish solid in 73.23 % yield; mp

96-98 ⁰C; IR (KBr) 1105 (C-N aromatic), 1621 (C-O chalcone), 1790, 2940 cm^–1; ¹H NMR (CDCl₃) : 2.60 (s,

3H), 7.38 (m, 3H, J = 15.10 Hz), 7.46 (t, 1H, J = 7.50 Hz), 7.76 (m, 1H), 7.78 (m, 1H, J = 15.10 Hz), 7.97 (m,

2H, J = 7.50), 8.04 (q, 1H), 8.09 (dt, 1H); ¹³C NMR (CDCl₃) : 26.8 (CH₃, C-20), 123.5 (CH=, C-9), 127.7

(CH, C-13 ), 128.2 (CH, C-12), 128.3 (CH, C-14), 128.9 (CH, C-2), 128.9 (CH, C-3), 129.6 (CH, C-4), 129.6

(CH, C-5), 130.0 (CH, C-16), 133.6 (C, C-11), 133.8 (C, C-1), 137.3 (C, C-15), 143.3 (C-N, C-6), 144.0 (CH=,

Page 19 of 37

New Journal of Chemistry

C-10), 191.7 (C=O, C-8), 197.7 (C=O, C-18); MS (M/Z) 312.0 [M]⁺; Anal Calcd for C₁₇H₁₃NO₅: C, 65.63; H,

5.05; N, 4.72 found C, 65.59; H, 4.94; N, 4.64.

View Article Online

DOI: 10.1039/C8NJ02077A

(E)-4-[3-(4-tert-butylphenyl)prop-2-enoyl]phenyl nitrate (AI8)

By following above methods, the title compound AI8 was obtained as a yellowish solid in 73.05 % yield; mp

0

108-110 C; IR (KBr) 1056 (C-N aromatic), 1585 (O-NO₂), 1641 (C-O chalcone), 1758 (C=C), 2940 (C-H

aromatic) cm^–1; ¹H NMR (CDCl₃) : 1.29 (s, 9H) 7.20 (t, 1H, J = 7.50 Hz), 7.38 (dd, 3H, J = 7.50 Hz), 7.47 (dt,

2H, J = 15.10 Hz), 7.54 (dt, 1H, J = 7.50 Hz), 7.65 (dt, 1H, J = 15.10 Hz), 7.97 (m, 2H, J = 7.50 Hz); ¹³C NMR

(CDCl) : 31.0 (CH₃, C-20), 31.0 (CH₃, C-21), 31.0 (CH₃, C-19), 34.8 (CH₃, C-18),123.5 (CH=, C-9),123.5

(CH, C-16), 124.5 (CH, C-12), 124.8 (CH, C-13), 128.6 (CH, C-14), 128.9 (CH, C-3), 128.9 (CH, C-2), 129.6

(CH, C-4), 129.6 (CH, C-5),133.7 (C, C-11), 133.8 (C, C-1), 143.3 (C-N, C-6),144.0 (C, C-10), 148.3 (C, C-

15), 191.7 (C=O, C-8); MS (m/z) 326.1[M]⁺; Anal Cacld for C₁₉H₁₉NO₄: C, 78.63; H, 5.58; N, 3.72 found C,

78.60; H, 5.94; N, 3.64.

General Procedure for synthesis of compound ii of scheme 1 and 2.

To a stirred solution of (i) in dichloromethane in ice-bath, a solution of K₂CO₃(6.30 mmol) was added. To this

solution bromoacetyl bromide (4.60 mmol) in 20 ml of dichloromethane was added in a drop wise manner,

while keeping over 30 min. The mixture was left for stirring for further 2 h. at 0⁰C and 24 h. at room

temperature. The organic layer was separated and aqueous layer was extracted with (2 x 30 ml) of

dichloromethane. The combined organic layer was washed consequently with distilled water. The organic layer

dried over anhydrous sodium sulphate, evaporated under reduced pressure and the obtained crude product was

recrystallized from ethanol.

General Procedure for synthesis of compounds Ca 1-8 of scheme 1.

To a stirred solution of bromoacetyl derivative (ii and iii) (10.0 mmol) in 20 ml acetonitrile, silver nitrate (40.00

mmol) was added. The mixture was heated for 13-17 h. at 80⁰C. The formed precipitate of silver bromide was

filtered off. The filtrate was evaporated till dryness and dissolved in dichloromethane; the organic layer was

washed consequently with distilled water (2 x 20 ml) and brine. The organic layer was dried over anhydrous

sodium sulphate, evaporated and crude product was recrystallized from methanol.

(E)-4-[3-(3-nitrophenyl)prop-2-enoyl]phenyl (nitrooxy)acetate (Ca1)

By following above methods, the title compound Ca1 was obtained as a yellow solid in 67.82 % yield; mp 82-

84 ⁰C; IR (KBr) 857, 1073 (C-N aromatic), 1648 (C-O chalcone), 1683 (C-O ester), 1720, 3270 cm^–1; ¹H NMR

(CDCl₃) : 2.49 (q, 2H, J = 8.00 Hz), 7.08 (m, 2H, J = 7.50 Hz), 7.67 (m, 1H, J = 15.10 Hz), 7.69 (m, 1H, J =

7.50 Hz), 7.76 (dt, 1H, J = 15.10 Hz), 7.96 (m, 1H, J = 7.50 Hz), 8.05 (m, 2H, J = 7.50 Hz), 8.39 (m, 1H), 8. 60

13

(q, 1H); C NMR (CDCl₃) : 27.3 (CH₂, C-20), 121.6 (CH, C-4), 121.6 (CH, C-5), 122.1 (CH, C-15), 123.5

(CH=, C-8), 124.7 (CH, C-12), 129.8 (CH, C-13), 130.8 (CH, C-2), 130.8 (CH, C-3), 132.5 (C, C-1), 134.2

(CH, C-11), 137.7 (C, C-10), 141.6 (CH, C-9), 147.7 (C-N, C-14), 154.5 (C-O, C-6), 172.5 (C=O, C-18), 185.5

(C=O, C-7); MS (m/z) 373.0 [M]⁺; Aanal Calcd for C₁₇H₁₂N₂O₈: C, 54.85; H, 3.25; N, 7.52 found C, 54.90; H,

3.55; N,71.29.

(E)-4-{3-[3,4-bis(hydroxymethyl)phenyl]prop-2-enoyl}phenyl (nitrooxy)acetate (Ca2)

New Journal of Chemistry

Page 20 of 37

By following above methods, the title compound Ca2 was obtained as a yellow solid in 71.29 % yield; mp 88-

0

1

90 C; IR (KBr) 834, 1102 (C-N aromatic), 1690 (C-O ester), 1765, 3320 cm^–1; H NMR (CDCl₃) : 2.49 (q,

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2H, J = 8.00 Hz), 4. 80 (d, 4H), 7.17 (m, 2H, J = 7.50 Hz), 7.44 (s, 2H, J = 7.50 Hz), 7.50 (m, 2H, J = 7.50 Hz),

DOI: 10.1039/C8NJ02077A

7.67 (d, 1H, J = 15.10 Hz), 8.09 (d, 2H, J = 7.50 Hz); ¹³C NMR (CDCl₃) : 27.3 (CH₂, C-20), 62.6 (CH₂, C-23),

62.8 (CH₂, C-22), 121.6 (CH, C-4), 121.6 (CH, C-5), 123.5 (CH=, C-8),127.4 (CH, C-12), 127.7 (CH, C-11)

129.3 (CH, C-13), 130.8 (CH, C-2), 130.8 (CH, C-3), 132.5 (CH, C-1), 132.9 (C, C-10), 136.3 (C, C-15), 138.5

(C, C-14), 144.0 (CH=, C-9),154.5 (CH-, C-6), 172.5 (C=O, C-18), 191.7 (C=O, C-7); MS (m/z) 388.1 [M]⁺;

Anal Calcd for C₁₉H₁₅NO₈: C, 58.92; H, 4.42; N, 3.62 found C, 58.78; H, 4.55; N, 3.54.

(E)-4-{3-[3,4,5-tris(hydroxymethyl)phenyl]prop-2-enoyl}phenyl (nitrooxy)acetate (Ca3)

By following above methods, the title compound Ca3 was obtained as a yellow solid in 60.21 % yield; mp 104-

0

106 C; IR (KBr) 748, 1100 (C-N aromatic), 1689 (C-O ester), 1720, 3270 cm^–1; ¹H NMR (CDCl₃) : 1.17 (t,

3H), 2.49 (q, 2H, J = 8.00 Hz), 4.80 (s, 6H), 7.17 (m, 2H, J = 7.50 Hz), 7.50 (m, 1H, J = 7.50 Hz), 7.52 (m, 2H),

7.67 (m, 2H), 8.07 (m, 2H, J = 7.50 Hz); ¹³C NMR (CDCl₃) : 27.6 (CH₂, C-20), 59.1 (CH₂, C-23), 63.3 (CH₂,

C-22), 63.3 (CH₂, C-26), 120.2 (CH, C-4), 120.2 (CH, C-5), 122.2 (CH=, C-8), 128.3 (CH, C-11), 128.3 (CH,

C-12), 131.0 (CH, C-2), 131.0 (CH, C-3), 132.3 (C, C-10), 133.2 (C, C-1), 138.4 (C, C-15), 139.8 (C, C-13),

139.8 (C, C-14), 140.1 (C-O, C-6), 143.7 (CH=, C-9), 172.5 (C=O, C-18), 185.6 (C=O, C-7); MS (m/z) 418.1

[M]⁺; Anal Calcd for C₂₀H₁₉N₂O₈: C, 57.55; H, 4.59; N, 3.36 found C, 57.60; H, 4.75; N, 3.41.

(E)-4-[3-(4-chlorophenyl)prop-2-enoyl]phenyl (nitrooxy)acetate (Ca5)

By following above methods, the title compound Ca5 was obtained as a yellow solid in 71.28 % yield; mp 110-

0

112 C; IR (KBr) 810, 1079 (C-N aromatic), 1695 (C-O ester), 1728, 2952 cm^–1; ¹H NMR (CDCl₃) : 2.49 (q,

2H, J = 8.00 Hz), 7.18 (m, 2H, J = 7.50 Hz), 7.69 (d, 1H, J = 15.10 Hz), 7.73 (m, 2H, J = 7.50 Hz), 7.78 (m, 1H,

13

J = 7.50 Hz), 8.10 (m, 2H, J = 7.50 Hz), 8.34 (m, 2H, J = 7.50 Hz); C NMR (CDCl₃) : 9.1 (CH, C-21), 27.6

(CH₂, C-20), 120.4 (CH, C-4), 120.4 (CH, C-5), 120.4 (CH=, C-8), 121.8 (C-Cl, C-15), 130.5 (CH, C-11),

130.8 (CH, C-12), 131.0 (CH, C-2), 131.0 (CH, C-3), 13.5 (CH, C-13), 131.5 (CH, C-14), 133.2 (C, C-1), 140.1

(C-O, C-6), 142.6 (CH=, C-9), 173.3 (C=O, C-18), 186.5 (C=O, C-7); MS (m/z) 362.0 [M]⁺; Anal Calcd for

C₁₇H₁₂ClNO₆: C, 56.45; H, 3.34; N, 3.87 found C, 56.66; H, 3.51; N, 3.71.

(E)-4-[3-(4-fluorophenyl)prop-2-enoyl]phenyl (nitrooxy)acetate (Ca7)

By following above methods, the title compound Ca7 was obtained as a white solid in 71.08 % yield; mp 142-

0

144 C; IR (KBr) 710, 1610 (C-O chalcone), 1690 (C-O ester), 1748, 2990 cm^–1; ¹H NMR (CDCl₃) : 2.49 (q,

2H, J = 8.00 Hz), 7.17 (m, 2H, J = 7.50 Hz), 7.45 (d, 1H, J = 15.10 Hz), 7.50 (m, 2H, J = 7.50), 7.57 (m, 2H, J =

13

15.10 Hz), 7.66 (m, 1H, J = 7.50 Hz), 8.08 (dt, 2H, J = 7.50 Hz); C NMR (CDCl₃) : 27.3 (CH₂, C-20), 120.4

(CH=, C-8), 121.6 (CH, C-4), 121.6 (CH, C-5), 129.2 (CH, C-13), 129.2 (CH, C-14), 129.7 (CH, C-11), 129.7

(CH, C-13), 130.8 (C, C-2), !30.8 (CH, C-3), 132.5 (CH, C-1), 133.4 (CH, C-10), 133.4 (C-F, C-15), 143.1

(C=C, C-9), 154.5 (C-O, C-6), 172.5 (C=O, C-8), 188.8 (C=O, C-7); MS (m/z) 362.0 [M]⁺; Anal for

C₁₇H₁₂FNO₆: C, 59.14; H, 3.50; N, 4.06 found C, 59.24; H, 3.38; N, 4.10.

(E)-4-[3-(3-chlorophenyl)prop-2-enoyl]phenyl (nitrooxy)acetate (Ca8)

Page 21 of 37

New Journal of Chemistry

By following above methods, the title compound Ca8 was obtained as a brown solid in 68.03 % yield; mp 108-

0

1

110 C; IR (KBr) 723, 1005 (C-N aromatic), 1670 (C-O chalcone), 1750 (aromatic), 3200 cm^–1; H NMR

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(CDCl₃) : 2.49 (q, 2H, J = 8.00 Hz), 7.09 (m, 2H, J = 7.50 Hz), 7.46 (m, 1H, J = 15.10 Hz), 7.48 (m, 1H, J =

DOI: 10.1039/C8NJ02077A

7.50 Hz), 7.49 (m, 1H), 7.64 (m, 1H), 7.65 (m, 1H), 7.67 (m, 1H), 8.04 (dt, 2H, J = 7.50 Hz); ¹³C NMR

(CDCl₃) : 27.3 (CH₂, C-20), 121.6 (CH, C-4), 121.6 (CH, C-5), 123.5 (CH=, C-8), 126.7 (CH, C-11), 127.4

(CH, C-15), 127.8 (CH, C-12), 130.2 (CH, C-13), 130.8 (CH, C-2), 130.8 (CH, C-3), 132.5 (CH, C-1), 135.3

(C-Cl, C-14), 136.8 (C, C-10), 142.8 (CH=, C-9), 154.5 (C-O, C-6), 172.5 (C-O, C-18), 185.5 (C-O, C-7); MS

(m/z) 362.0 [M]⁺; Anal for C₁₇H₁₂ClNO₆: C, 56.45; H, 3.34; N, 3.83 found C, 56.47; H, 3.38; N, 3.80.

General procedure of synthesis of compounds AII1-8 of scheme 2.

The procedure is similar as that of synthesis of compound AI1-8 of scheme 1.

(E)-4-[3-(4-bromophenyl)-3-oxoprop-1-en-1-yl]phenyl nitrate (AII1)

By following above methods, the title compound AII1 was obtained as a whitish brown solid in 73.54 % yield;

0

mp 110-112 C; IR (KBr) 745, 1075 (C-N aromatic), 1630 (C-O chalcone), 1720 (aromatic), 2972 cm^–1; ¹H

NMR (CDCl₃) : 7.21 (m, 2H, J = 7.50 Hz), 7.36 (m, 2H, J = 7.50 Hz), 7.48 (d, 1H, J = 15.10 Hz), 7.69 (m, 1H,

J = 15.10 Hz), 7.75 (m, 2H, J = 7.50 Hz), 8.00 (m, 2H, J = 7.50 Hz); ¹³C NMR (CDCl₃) : 120.4 (CH=, C-9),

127.2 (C-Br, C-16), 129.4 (CH, C-2), 129.4 (CH, C-3), 129.7 (CH, C-4), 129.7 (CH, C-5), 130.1 (CH, C-12),

130.1 (CH, C-13), 131.4 (CH, C-14), 131.4 (CH, C-15), 132.1 (C, C-1), 136.8 (C, C-11), 138.7 (C-N, C-6),

143.6 (CH=, C-8) 188.9 (C=O, C-10); MS (m/z) 347.9 [M]⁺; Anal Calcd for C₁₅H₁₀BrNO₄: C, 56.26; H, 3.15;

N, 7.29 found C, 56.08; H, 3.11; N, 7.24.

(E)-4-[3-(3-nitrophenyl)-3-oxoprop-1-en-1-yl]phenyl nitrate (AII2)

By following above methods, the title compound AII2 was obtained as a yellow solid in 69.03 % yield; mp

0

1

122-124 C; IR (KBr) 857, 1093 (C-N aromatic), 1670 (C-O chalcone), 2972, 3350 (N-O, nitrite) cm^–1; H

NMR (CDCl₃) : 7.21 (m, 2H, J = 7.50 Hz) 7.38 (m, 2H, J = 7.50 Hz), 7.45 (d, 1H, J = 15.10 Hz), 7.64 (m, 1H,

13

J = 15.10 Hz), 7.66 (m, 1H), 8.47 (m, 1H, J = 7.50 Hz), 8.48 (m, 1H, J = 7.50 Hz), 8.69 (t, 1H, J = 7.50 Hz); C

NMR (CDCl₃) : 121.9 (CH=, C-9), 123.2 (CH, C-13), 127.2 (CH, C-16), 129.4 (CH, C-2), 129.4 (CH, C-3),

129.7 (CH, C-4), 129.7 (CH, C-5), 130.6 (CH, C-14), 132.1 (C, C-1), 134.1(CH, C-12), 138.7 (C-N, C-6),

139.6 (C, C-11), 143.9 (CH=, C-8), 148.5 (C-N, C-15), 187.8 (C=O, C-10); MS (m/z) 315.0 [M]⁺; Anal Calcd

for C₁₅H₁₀N₂O₆: C, 61.79; H, 4.09; N, 3.79 found C, 61.52; H, 4.06; N, 3.70.

(E)-4-{3-[2,5-bis(hydroxymethyl)phenyl]-3-oxoprop-1-en-1-yl}phenyl nitrate (AII3)

By following above methods, the title compound AII3 was obtained as a yellow solid in 64.17 % yield; mp

120-122 ⁰C; IR (KBr) 1100 (C-N aromatic), 1670 (C-O chalcone), 1705, 2953 cm^–1; ¹H NMR (CDCl₃) : 2.30

(s, 2H), 4.41 (d, 2H), 4.80 (d, 2H), 7.21 (m, 2H, J = 7.50 Hz), 7.38 (m, 2H, J = 7.50 Hz), 7.41 (d, 1H, J = 15.10

Hz), 7.58 (dt, 1H), 7.65 (dd, 1H, J = 15.10 Hz), 7.71 (ddt, 1H, J = 7.50 Hz), 7.92 (t, 1H, ArH); ¹³C NMR

(CDCl₃) : 62.0 (CH₂, C-18), 64.5 (CH₂, C-19), 120.7 (CH=, C-9), 125.0 (CH, C-16), 128.8 (CH, C-15), 129.4

(CH, C-2), 129.4 (CH, C-3), 129.7 (CH, C-4), 129.7 (CH, C-5), 130.5 (C, C-1), 131.4 (CH, C-12), 137.4 (C, C-

14), 138.7 (C-N, C-6), 139.6 (C, C-13), 143.8 (C, C-11), 144.0 (CH=, C-8), 193.9 (C=O, C-10); MS (m/z)

New Journal of Chemistry

Page 22 of 37

330.0 [M]⁺; Anal Calcd for C₁₇H₁₅NO₆: C, 60.15; H, 4.29; N, 3.51. found C, 60.13; H, 4.25; N, 3.50. 4-[(1E)-

(E)-4-[3-(4-nitrophenyl)-3-oxoprop-1-en-1-yl]phenyl nitrate (AII4)

View Article Online

By following above methods, the title compound AII4 was obtained as a yellow solid in 67.81 % yield; mp

DOI: 10.1039/C8NJ02077A

102-104 ⁰C; IR (KBr) 1075 (C-N aromatic), 1670 (C-O chalcone), 1702, 2900, 2972 cm^–1; ¹H NMR (CDCl₃) :

7.21 (m, 2H, J = 7.50 Hz), 7.36 (m, 2H, J = 7.50 Hz), 7.45 (d, 1H, J = 15.10 Hz), 7.65 (m, 1H, J = 15.10 Hz),

13

8.12 (m, 2H, J = 7.50 Hz), 8.26 (m, 2H, J = 7.50 Hz); C NMR (CDCl₃) : 120.4 (CH=, C-9), 125.2 (CH, C-

14), 125.2 (CH, C-15), 129.4 (CH, C-2), 129.4 (CH, C-3), 129.7 (CH, C-4), 129.7 (CH, C-5), 130.1 (CH, C-

12), 130.1 (CH, C-13), 132.1 (C, C-1), 138.7 (C-N, C-6), 143.0 (C, C-11), 143.6 (CH=, C-8), 150.0 (C-N, C-

16), 188.9(C=O, C-10); MS (m/z) 315.0 [M]⁺; Anal Calcd for C₁₅H₁₀N₂O₆: C, 65.39; H, 4.66; N, 3.81 found C,

65.34; H, 4.61; N, 3.87.

(E)-4-[3-(4-methylphenyl)-3-oxoprop-1-en-1-yl]phenyl nitrate (AII5)

By following above methods, the title compound AII5 was obtained as a yellow solid in 67.12 % yield; mp 96-

0

1

98 C; IR (KBr) 1075 (C-N aromatic), 1690 (C-O chalcone), 1770, 2980 cm^–1; H NMR (CDCl₃) : 7.21 (m,

2H, J = 7.50 Hz), 7.37 (ddt, 2H, J = 7.50 Hz), 7.38 (d, 2H, J = 7.50 Hz), 7.45 (dt, 1H, J = 15.10 Hz), 7.65 (m, H,

13

J = 15.10 Hz), 7.97 (m, 2H, J = 7.50 Hz); C NMR (CDCl₃) : 21.4 (CH₃, C-18), 120.4 (CH=, C-9), 128.9

(CH, C-12), 128.9 (CH, C-13), 129.4 (CH, C-2), 129.4 (CH, C-3), 129.7 (CH, C-14), 129.7 (CH, C-15), 129.7

(CH, C-4), 129.7 (CH, C-5), 132.1 (C, C-1), 133.8 (C, C-11), 138.7 (C-N, C-6), 143.3 (C, C-16), 143.6 (CH=,

C-8), 188.2 (C=O, C-10); MS (m/z); 284.0 [M] ⁺; Anal Calcd for C₁₆H₁₃NO₄: C, 65.18; H, 4.88; N, 3.51 found

C, 65.24; H, 4.81; N, 3.78.

(E)-4-{3-[3,4-bis(hydroxymethyl)phenyl]-3-oxoprop-1-en-1-yl}phenyl nitrate (AII7)

By following above methods, the title compound AII7 was obtained as a yellow solid in 68.83 % yield; mp

120-122 ⁰C; IR (KBr) 1089 (C-N aromatic), 1600 (C-O chalcone), 1740, 2900 cm^–1; ¹H NMR (CDCl₃) : 2.30

(m, 2H), 4.53 (d, 4H), 7.21 (m, 2H, J = 7.50 Hz), 7.38 (m, 2H, J = 7.50 Hz), 7.45 (m, 2H, J = 15.10), 7.65 (dt,

1H, J = 15.10 Hz), 7. 86 (dt, 1H), 8.08 (dd, 1H, J = 7.50 Hz); ¹³C NMR (CDCl₃) : 62.7 (CH, C-18), 62. 7 (CH,

C-20), 121.9 (CH=, C-9), 128.1 (CH, C-15), 128.2 (CH, C-13), 128.3 (CH, C-12), 129.4 (CH, C-2), 129.4 (CH,

C-3), 129.7 (CH, C-4), 129.7 (CH, C-5), 132.1 (C, C-1), 136.3 (C-C, C-16), 138.0 (C, C-11), 138.5 (C-C, C-

14), 138.7 (C-N, C-6), 143.9 (CH=, C-8), 190.7 (C=O, C-10); MS (m/z) 330.0 [M]⁺; Anal Calcd for

C₁₇H₁₅NO₆: C, 65.00; H, 4.45; N, 3.91 found C, 65.04; H, 4.81, N, 3.78.

(E)-4-[3-(4-ethylphenyl)-3-oxoprop-1-en-1-yl]phenyl nitrate (AII8)

By following above methods, the title compound AII8 was obtained as a yellow solid in 68.23 % yield; mp

130-132 ⁰C; IR (KBr) 1090 (C-N aromatic), 1648 (C-O chalcone), 1710, 2900, 2992 cm^–1; ¹H NMR (CDCl₃) :

1.19 (t, 3H, J = 8.00 Hz), 2.67 (tdd, 2H, J = 8.00 Hz), 7.21 (m, 2H, J = 7.50 Hz), 7.35 (m, 2H, J = 7.50 Hz),

13

7.37 (m, 2H, J = 7.50 Hz), 7.45 (m, 1H, J = 15.10), 7.65 (dt, 1H, J = 15.10 Hz), 7.90 (dt, 2H, J = 7.50 Hz); C

NMR (CDCl₃) : 15.5 (CH_3,C-19), 28.6 (CH₂, C-18), 120.4 (CH=, C-9), 127.6 (CH, C-12), 127.60 (CH, C-13),

128.6 (CH, C-14), 128.6 (CH, C-15), 129.4 (CH, C-2), 129.4 (CH, C-3), 129.7 (CH, C-4), 129.7 (CH, C-5),

132.1 (C, C-1), 136.7 (C, C-11), 138.7 (C, C-6), 143.6 (CH=, C-8), 146.4 (C, C-16), 185.4 (C=O, C-10); MS

(m/z) 298.1[M]⁺; Anal Calcd for C₁₇H₁₅NO₄: C, 64.80; H, 4.40; N, 3.80 found C, 64.01; H, 4.85; N, 3.76.

Page 23 of 37

New Journal of Chemistry

General Procedure for synthesis of compounds Cb2-5 of scheme 2.

The procedure is similar as that of synthesis of compounds Ca1-7 of scheme 1.

View Article Online

DOI: 10.1039/C8NJ02077A

(E)-4-{3-[2,4-bis(hydroxymethyl)phenyl]-3-oxoprop-1-en-1-yl}phenyl (nitrooxy)acetate (Cb2)

By following above methods, the title compound Cb2 was obtained as a yellow solid in 72.72 % yield; mp 102-

104 ⁰C; IR (KBr) 830, 1600 (C-O ester), 1690 (C-O chalcone), 1700, 3220 cm^–1; ¹H NMR (CDCl₃) : 1.21 (dt,

2H), 2.49 (q, 2H, J = 8.00 Hz), 4.80 (m, 2H), 4.81 (m, 2H), 7.08 (m, 2H, J = 7.50 Hz), 7.41 (d, 1H, J = 15.10

Hz), 7.53 (dt, 1H), 7.57 (m, 1H, J = 7.50 Hz), 7.61 (m, 2H, J = 7.50 Hz), 7.66 (dt, 1H, J = 15.10 Hz), 7.89 (d,

1H, J = 7.50 Hz); ¹³C NMR (CDCl₃) : 27.3 (CH₂, C-20), 62.8 (CH₂, C-22), 64.2 (CH₂, C-23), 120.7 (CH=, C-

8), 122.0 (CH, C-4), 122.0 (CH, C-5), 124.6 (CH, C-13), 129.1 (CH, C-14), 129.2 (C, C-1), 129.5 (CH, C-2),

129.5 (CH, C-3), 130.1 (CH, C-11), 136.9 (C, C-15), 138.5 (C, C-10), 142.0 (C, C-12), 144.0 (CH=, C-7),

152.0 (C-O, C-6), 172.5 (C=O, C-18), 193.9 (C=O, C-9); MS (m/z) 388.1 [M]⁺; Anal Calcd for C₁₉H₁₇NO₈: C,

58.92; H, 4.42; N, 3.62 found C, 58.90; H, 4.40; N, 3.51.

(E)-4-{3-[4-(hydroxymethyl)phenyl]-3-oxoprop-1-en-1-yl}phenyl (nitrooxy)acetate (Cb3)

By following above methods, the title compound Cb3 was obtained as a yellow solid in 57.21 % yield; mp 98-

100 ⁰C; IR (KBr) 780, 1600 (C-O ester), 1680 (C-O chalcone), 1710, 3280 cm^–1; ¹H NMR (CDCl₃) : 1.12 (m.

1H), 2.49 (q, 2H, J = 8.00 Hz), 4.53 (d, 2H), 7.15 (m, 2H, J = 7.50 Hz), 7.48 (d, 1H, J = 8.00 Hz), 7.58 (dt, 2H,

13

J = 7.50 Hz), 7.64 (m, 2H, J = 15.10 Hz), 7.67 (m,1H), 7.95 (m, 2H, J = 7.50 Hz); C NMR (CDCl₃) : 27.3

(CH₂, C-20), 64.7 (CH₂, C-22), 120.4 (CH=, C-8), 122.0 (CH, C-4), 122.0 (CH, C-5), 127.3 (CH, C-11), 127.3

(CH, C-12), 128.2 (CH, C-13), 128.2 (CH, C-14), 128.7 (C, C-1), 129.5 (CH, C-2), 129.5 (CH, C-3), 137.9 (C,

C-10), 144.9 (CH=, C-7), 145.3 (C, C-15), 152.0 (C-O, C-6), 172.5 (C=O, C-18), 185.4 (C=O, C-9); MS (m/z)

358.0[M]⁺; Anal Calcd for C₁₈H₁₅NO₇: C, 60.50; H, 4.23; N, 3.92 found C, 60.61; H, 4.11; N, 3.78.

(E)-4-[3-(3,4-dichlorophenyl)-3-oxoprop-1-en-1-yl]phenyl (nitrooxy)acetate (Cb4)

By following above methods, the title compound Cb4 was obtained as a yellow solid in 70.23 % yield; mp 110-

0

112 C; IR (KBr) 790, 1620 (C-O ester), 1690 (C-O chalcone), 1760, 2900 cm^–1; ¹H NMR (CDCl₃) : 2.49 (q,

2H, J = 8.00 Hz), 7.15 (m, 2H, J = 7.50 Hz), 7.47 (d, 1H, J = 7.50 Hz), 7.49 (m, 2H, J = 8.00 Hz), 7.65 (m, 1H),

7.67 (dt, 2H, J = 15.10 Hz), 8.14 (d, 1H, J = 7.50 Hz); ¹³C NMR (CDCl₃) : 27.3 (CH₂, C-20), 121.9 (CH=, C-

8), 122.0 (CH, C-4), 122.0 (CH, C-5), 127.6 (CH, C-11), 128.7 (C, C-1), 128.7 (CH, C-12), 129.5 (CH, C-2),

129.5 (CH, C-3), 129.9 (CH, C-13), 132.8 (C-Cl, C-14), 134.3 (C-Cl, C-15), 136.3 (C, C-10), 144.0 (CH=, C-

7), 152.0 (C-O, C-6), 172.5 (C=O, C-18), 190.7 (C=O, C-9); MS (m/z) 396.0 [M]⁺; Anal Calcd for

C₁₇H₁₁Cl₂NO₆: C, 51.54; H, 2.80; N, 3.54 found C, 51.46; H, 2.65; N, 3.37.

(E)-4-[3-(4-ethylphenyl)-3-oxoprop-1-en-1-yl]phenyl (nitrooxy)acetate (Cb5)

By following above methods, the title compound Cb5 was obtained as a yellow solid in 63.82 % yield; mp 92-

0

94 C; IR (KBr) 800, 1610 (C-O ester), 1680 (C-O chalcone), 1738, 3012 cm^–1; ¹H NMR (CDCl₃) : 1.19 (dt,

3H, J = 8.00 Hz), 2.49 (q, 2H, J = 8.00 Hz), 2.67 (tdd, 2H, J = 8.00 Hz), 7.15 (m, 2H, J = 7.50 Hz), 7.35 (dt, 2H,

J = 7.50 Hz), 7.47 (d, 1H, J = 15.10 Hz), 7.63 (m, 2H, J = 15.10 Hz), 7.67 (m, 1H), 7.90 (m, 2H, J = 7.50 Hz);

¹³C NMR (CDCl₃) : 15.5 (CH₃, C-23), 27.3 (CH₂, C-20), 28.6 (CH₂, C-22), 120.4 (CH=, C-8), 122.0 (CH, C-

4), 122.0 (CH, C-5), 127.6 (CH, C-11), 127.6 (CH, C-12), 128.6 (CH, C-13), 128.6 (CH, C-14), 128.7 (C, C-1),

New Journal of Chemistry

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129.5 (CH, C-2), 129.5 (CH, C-3), 136.7 (C, C-10), 144.9 (CH=, C-7), 146.4 (C, C-15), 152.0 (C-O, C-6),

172.5 (C-O, C-18), 185.4 (C-O, C-9); MS (m/z) 356.1 [M]⁺; Anal Calcd for C₁₉H₁₇NO₆: C, 64.22; H, 4.82; N,

View Article Online

DOI: 10.1039/C8NJ02077A

3.94 found C, 64.33; H, 4.70; N, 3.87.

General Procedure for synthesis of compound ii of scheme 3

The procedure is similar to that of synthesis of compound ii of scheme 1 and 2.

General Procedure for synthesis of compound B2 – B11 of scheme 2

The procedure is similar to that of synthesis of compounds Ca1-7 and Cb1-5 of scheme 1 and 2.

(E)-2-({4-[3-(2-nitrophenyl)prop-2-enoyl]phenyl}amino)-2-oxoethyl nitrate (B2)

By following above methods, the title compound B2 was obtained as a yellow solid in 67.34 % yield; mp 122-

0

1

124 C; IR (KBr) 864, 1602 (C-O amino ester), 1690 (C-O chalcone), 3320 (N-H amide) cm^–1; H NMR

(CDCl₃) : 1.12 (t, 1H), 2.35 (q, 2H, J = 8.00 Hz), 7.24 (m, 2H, J = 7.50 Hz), 7.57 (m, 1H, J = 7.50 Hz), 7.60

(dt, 1H). 7.70 (m, 1H, J = 7.50 Hz), 7.80 (ddd, 1H, J = 7.50 Hz), 7.96 (m, 2H, J = 7.50 Hz), 8.06 (dd, 1H, J =

15.10 Hz), 8.25 (dd, 1H, J = 7.50 Hz); ¹³C NMR (CDCl₃) : 27.6 (CH₂, C-20), 120.2 (CH, C-4), 120.2 (CH, C-

5), 124.8 (CH=, C-8), 128.8 (CH, C-15), 129.6 (CH, C-14), 131.0 (CH, C-2), 131.0 (CH, C-3), 132.3 (CH, C-

11), 132.7 (C, C-10), 132.8 (CH, C-13), 133.5 (C, C-1), 140.1 (C-N, C-6), 141.7 (CH=, C-9), 149.4 (C-N, C-

12), 173.3 (C-O, C-18), 190.2 (C-O, C-7); MS (m/z) 372.0[M]⁺; Anal Calcd for C₁₇H₁₃N₃O₇: C, 55.99; H,

3.53; N, 11.32 found C, 56.06; H, 3.50; N, 11.34.

(E)-2-({4-[3-(2-chlorophenyl)prop-2-enoyl]phenyl}amino)-2-oxoethyl nitrate (B3)

By following above methods, the title compound B3 was obtained as a yellow solid in 69.03 % yield; mp 122-

124 ⁰C; IR (KBr) 760, 1100, 1640 (C-O amino ester), 1700, 3270 (N-H amide) cm^–1; ¹H NMR (CDCl₃) : 1.12

(t, 1H), 2.35 (q, 2H, J = 8.00 Hz), 7.22 (m, 2H, J = 7.50 Hz), 7.27 (m, 1H, J = 7.50 Hz), 7.31 (m, 1H, J = 15.10

Hz), 7.36 (m, 1H, J = 7.50 Hz), 7.38 (m, 1H, J = 7.50 Hz), 7.46 (dd, 1H, , J = 7.50 Hz), 7.85 (dd, 1H, J = 15.10

13

Hz), 7.91 (dd, 2H, J = 7.50 Hz); C NMR (CDCl₃) : 27.6 (CH₂, C-20), 120.2 (CH, C-4), 120.2 (CH, C-5),

123.8 (CH=, C-8), 127.5 (CH, C-13), 128.5 (CH, C-11), 129.5 (CH, C-14), 130.6 (CH, C-15), 131.0 (CH, C-2),

131.0 (CH, C-3), 132.5 (C, C-10), 133.1 (C-Cl, C-12), 133.5 (C, C-1), 138.8 (CH=, C-9), 140.1 (C-N, C-6),

173.3 (C-O, C-18), 190.2 (C-O, C-7); MS (m/z) 361.0 [M]⁺; Anal Calcd for C₁₇H₁₃ClN₂O₅: C, 56.60; H, 3.63;

N, 7.77 found C, 56.58; H, 3.55; N, 7.71.

(E)-2-({4-[3-(4-fluorophenyl)prop-2-enoyl]phenyl}amino)-2-oxoethyl nitrate (B4)

By following above methods, the title compound B4 was obtained as a yellow solid in 67.03 % yield; mp 128-

130 ⁰C; IR (KBr) 750, 1670 (C-O amino ester), 1705, 1751, 3200 (N-H amide) cm^–1; ¹H NMR (CDCl₃) : 1.12

(t, 1H), 2.35 (q, 2H, J = 8.00 Hz), 7.23 (m, 2H, J = 7.50 Hz), 7.32 (m, 2H, J = 7.50 Hz), 7.40 (d, 1H, J = 15.10),

7.52 (d, 2H, J = 7.50 Hz), 7.65 (dt, 1H, J = 15.10 Hz), 7.92 (m, 2H, J = 7.50 Hz); ¹³C NMR (CDCl₃) : 27.6

(CH₂, C-20), 114.7 (CH, C-13), 114.7 (CH, C-14), 120.2 (CH, C-4), 120.2 (CH, C-5), 120.4 (CH=, C-8), 130.2

(CH, C-11), 130.2 (CH, C-12), 131.0 (CH, C-2), 131.0 (CH, C-3), 131.1 (C, C-10), 133.2 (C, C-1), 140.1 (C-N,

C-6), 143.3 (CH, C-9), 163.2 (C-F, C-15), 173.3 (C-O, C-18), 186.5 (C-O, C-7); MS (m/z) 345.0 [M]⁺; Anal

Calcd for C₁₇H₁₃FN₂O₅: C, 59.30; H, 3.81; N, 8.14 found C, 59.43; H, 3.68, N, 8.17.

(E)-2-({4-[3-(4-nitrophenyl)prop-2-enoyl]phenyl}amino)-2-oxoethyl nitrate (B5)

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New Journal of Chemistry

By following above methods, the title compound B5 was obtained as a yellow solid in 68.23 % yield; mp 188-

120 ⁰C; IR (KBr) 815, 1640 (C-O amino ester), 1690 (C-O chalcone), 1738, 3352 (N-H, amide) cm^–1; ¹H NMR

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(CDCl₃) : 1.12 (t, 1H), 2.35 (q, 2H, J = 8.00 Hz), 7.25 (m, 2H, J = 7.50 Hz), 7.71 (m, 1H), 7.75 (m, 2H, J =

DOI: 10.1039/C8NJ02077A

7.50 Hz), 7.78 (m,1H), 7.95 (m, 2H, J = 7.50 Hz), 8.35 (m, 2H, J = 7.50 Hz); ¹³C NMR (CDCl₃) : 27.6 (CH₂,

C-20), 120.2 (CH, C-4), 120.2 (CH, C-5), 120.4 (CH=, C-8), 124.6 (CH, C-13), 124.6 (CH, C-14), 129.0 (CH,

C-11), 129.0 (CH, C-12), 131.0 (CH, C-2), 131.0 (CH, C-3), 133.2 (C, C-1), 140.1 (C-N, C-6), 141.1 (C, C-10),

141.9 (CH=, C-9), 147.1 (C-N, C-15), 173.3 (C-O, C-18), 186.5(C-O, C-7); MS (m/z) 372.0 [M]⁺; Anal Calcd

for C₁₇H₁₃N₃O₇: C, 54.99; H, 3.53; N, 11.32. found C, 55.08; H, 3.57; N, 11.20.

(E)-2-({4-[3-(4-bromophenyl)prop-2-enoyl]phenyl}amino)-2-oxoethyl nitrate (B6)

By following above methods, the title compound B6 was obtained as a yellow solid in 56.72 % yield; mp 134-

136 ⁰C; IR (KBr) 810, 1641 (C-O amino ester), 1680 (C-O chalcone), 1782, 3260 (N-H, amide) cm^–1; ¹H NMR

(CDCl₃) : 1.12 (t, 1H), 2.35 (q, 2H, J = 8.00 Hz), 7.23 (m, 2H, J = 7.50 Hz), 7.41 (m, 2H, J = 7.50 Hz), 7.44

13

(m,1H), 7.65 (m, 1H, J = 15.10 Hz), 7. 69 (m, 2H, J = 7.50 Hz), 7.91 (m, 2H, J = 7.50 Hz); C NMR (CDCl₃)

: 27.6 (CH₂, C-20), 120.2 (CH, C-4), 120.2 (CH, C-5), 120.4 (CH=, C-8), 121.8 (C-Br, C-15), 130.5 (CH, C-

11), 130.5 (CH, C-12), 131.0 (CH, C-2), 131.0 (CH, C-3), 131.5 (CH, C-13), 131.5 (CH, C-14), 133.2 (C, C-

1), 133.8 (C, C-10), 140.1 (C-N, C-6), 142.6 (CH=, C-9), 173.3 (C-O, C-18), 186.5 (C-O, C-7); MS (m/z) 405.0

[M]⁺; Anal Calcd for C₁₇H₁₃BrN₂O₅: C, 50.39; H, 3.23; N, 6.91 found C, 50.48; H, 3.14; N, 6.85.

(E)-2-({4-[3-(4-acetylphenyl)prop-2-enoyl]phenyl}amino)-2-oxoethyl nitrate (B7)

By following above methods, the title compound B7 was obtained as a yellow solid in 66.12 % yield; mp 110-

0

112 C; IR (KBr) 700, 1614 (C-O amino ester), 1662 (C-O chalone), 1780, 3260 (N-H amide) cm^–1; ¹H NMR

(CDCl₃) : 1.12 (t, 1H), 2.35 (q, 2H, J = 8.00 Hz), 2.51 (dt, 3H, J = 8.00 Hz), 7.23 (m, 2H, J = 7.50 Hz), 7.49

(d, 1H, J = 15.10 Hz), 7.56 (m, 2H), 7.69 (dt, 1H, J = 15.10 Hz), 7.92 (m, 2H, J = 7.50 Hz), 7.96 (m, 2H, J =

7.50 Hz); ¹³C NMR (CDCl₃) : 26.8 (CH₃, C-24), 27.6 (CH₂, C-20), 120.2 (CH, C-4), 120.2 (CH, C-5), 120.4

(CH=, C-8), 128.3 (CH, C-11), 128.3 (CH, C-12), 128.4 (CH, C-13), 128.4 (CH, C-14), 131.0 (CH, C-2), 131.0

(CH, C-3), 133.2 (C, C-1), 134.1 (C, C-10), 138.5 (C, C-15), 140.1 (C-N, C-6), 143.9 (CH=, C-9), 173.3 (C-O,

C-18), 186.5 (C-O, C-7), 197.6 (C-O, C-22); MS (m/z) 369.1 [M]⁺; Anal Calcd for C₁₉H₁₆N₂O₆: C, 61.95; H,

4.38; N, 7.61 found C, 61.90; H, 4.28; N, 7.56.

(E)-2-({4-[3-(4-tert-butylphenyl)prop-2-enoyl]phenyl}amino)-2-oxoethyl nitrate (B8)

By following above methods, the title compound B8 was obtained as a yellow solid in 70.23 % yield; mp 132-

134 ⁰C; IR (KBr) 800, 1078, 1610 (C-O, amino ester), 1650 (C-O chalcone), 1720, 3220 (C-N amide) cm^–1; ¹H

NMR (CDCl₃) : 1.12 (m, 1H), 1.28 (s, 9H), 2.35 (q, 2H, J = 8.00 Hz) 7.23 (m, 2H, J = 7.50 Hz), 7.38 (m, 2H, J

= 7.50 Hz), 7.44 (d, 1H, J = 15.10 Hz), 7.48 (m, 2H, J = 7.50 Hz), 7.65 (dt, 1H, J = 15.10 Hz), 7.92 (m, 2H, J =

7.50 Hz); ¹³C NMR (CDCl₃) : 27.6 (CH₂, C-20), 31.1 (CH₃, C-23), 31.1 (CH₃, C-24), 31.1 (CH₃, C-25), 34.1

(C, C-22), 120.2 (CH, C-4), 120.2 (CH, C-5), 120.4 (CH=, C-8), 126.0 (CH, C-13), 126.0 (CH, C-14), 126.4

(CH, C-11), 126.4 (CH, C-12), 131.0 (CH, C-2), 131.0 (CH, C-3), 132.6 (C, C-10), 133.2 (C, C-1), 137.6 (C,

C-15), 140.1 (C-N, C-6), 143.9 (CH=, C-9), 173.3 (C-O, C-18), 186.5 (C-O, C-7); MS (m/z) 341.1 [M]⁺. Anal

Calcd for C₂₁H₂₂N₂O₅: C, 65.96; H, 5.80; N, 7.33 found C, 65.85; H, 5.78; N, 7.22.

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Page 26 of 37

(E)-2-({4-[3-(4-methylphenyl)prop-2-enoyl]phenyl}amino)-2-oxoethyl nitrate (B9)

By following above methods, the title compound B9 was obtained as a yellow solid in 74.91 % yield; mp 130-

_{View Article On}–_l1_ine1

132 ⁰C; IR (KBr) 830, 1078, 1600 (C-O amino ester), 1690 (C-O chalcone), 1700, 3220 (C-N amide) cm ; H

DOI: 10.1039/C8NJ02077A

NMR (CDCl₃) : 2.30 (q, 3H), 2.35 (m, 2H, J = 8.00 Hz), 7.21 (m, 2H, , J = 7.50 Hz), 7.24 (m, 2H, J = 7.50

Hz), 7.38 (m, 2H, J = 7.50 Hz), 7.48 (m, 1H, J = 15.10 Hz), 7.64 (dt, 2H, J = 15.10 Hz), 7.95 (m, 2H, J = 7.50

Hz); ¹³C NMR (CDCl₃) : 21.7 (CH₃, C-22), 27.6 (CH₂, C-20), 120.2 (CH, C-4), 120.2 (CH, C-5), 120.4 (CH=,

C-8), 129.4 (CH, C-11), 129.4 (CH, C-12), 129.7 (CH, C-13), 129.7 (CH, C-14), 131.0 (CH, C-2), 131.0 (CH,

C-3), 132.1 (C, C-10), 133.2 (C, C-1), 138.7 (C, C-15), 140.1 (C-N, C-6), 143.6 (=CH, C-9), 173.3 (C-O, C-

18), 186.5 (C-O, C-7); MS (m/z) 341.1 [M]⁺; Anal Calcd Anal for C₁₈H₁₆N₂O₅: C, 63.52; H, 4.74; N, 8.23

found C, 63.50; H, 4.64; N, 8.21.

(E)-2-[(4-{3-[3,4-bis(hydroxymethyl)phenyl]prop-2-enoyl}phenyl)amino]-2-oxoethyl nitrate (B10)

By following above methods, the title compound B10 was obtained as a yellow solid in 72.01 % yield; mp 140-

0

1

142 C; IR (KBr) 780, 1100, 1680 (C-O, chalcone), 1740, 3260 (C-N amide) cm^–1; H NMR (CDCl₃) : 1.12

(m, 3H), 2.35 (q, 2H, J = 8.00 Hz, -CH₂), 4.80 (m, 4H, J = 8.00 Hz), 7.24 (d, 2H, J = 7.50 Hz), 4.43 (m, 1H, J =

7.50 Hz), 7.45 (d, 1H, J = 7.50 Hz), 7.50 (m, 1H, J = 15.10 Hz), 7.52 (m, 1H, J = 15.10 Hz), 7.66 (dd, 1H, J =

15.10), 7.94 (m, 2H, J = 7.50 Hz); ¹³C NMR (CDCl₃) : 27.6 (CH₂, C-20), 62.6 (CH₂, C-23), 62.8 (CH₂, C-22),

120.2 (CH, C-4), 120.2 (CH, C-5), 123.5 (CH=, C-8), 127.4 (CH, C-12), 127.9(CH, C-11), 129.3 (CH, C-13),

131.0 (CH, C-2), 131.0 (CH, C-3), 133.2 (C, C-1), 132.9 (C, C-10), 136.3 (C, C-15), 138.5 (C, C-18), 140.1 (C-

N, C-6), 144.0 (=CH, C-9), 173.3 (C-O, C-18), 187.9 (C-O, C-7); MS (m/z) 387.1 [M]⁺; Anal Calcd for

C₁₉H₁₈N₂O₇: C, 59.07; H, 4.70; N, 7.25. found C, 59.12; H, 4.71; N, 7.28.

(E)-2-oxo-2-[(4-{(3-[3,4,5-tris(hydroxymethyl)phenyl]prop-2-enoyl}phenyl)amino]ethyl nitrate (B11)

By following above methods, the title compound B11 was obtained as a yellow solid in 68.90 % yield; mp 156-

158 ⁰C; IR (KBr) 784, 1154, 1680 (C-O chalone), 1750, 3260 (C-N amide) cm^–1; ¹H NMR (CDCl₃) : 1.12 (m,

4H), 2.35 (q, 2H, J = 8.00 Hz), 4.80 (s, 6H), 7.23 (m, 2H, J = 7.50 Hz), 7.48 (m, 1H), 7.52 (m, 2H, J = 15.10

Hz), 7.68 (dd, 1H, J = 15.10 Hz), 7.91 (m, 2H, J = 7.50 Hz); ¹³C NMR (CDCl₃) : 27.6 (CH₂, C-20), 59.1 (CH₂,

C-23), 63.3 (CH₂, C-22), 63.3 (CH₂, C-26), 120.2 (CH, C-4), 120.2 (CH, C-5), 122.2 (CH=, C-8), 128.3 (CH,

C-11), 128.3 (CH, C-12), 131.0 (CH, C-2), 131.0 (CH, C-3), 132.3 (C, C-10), 133.2 (C, C-1), 138.4 (C, C-15),

139.8 (C, C-13), 139.8 (C, C-14), 140.1 (C-N, C-6), 143.7 (=CH, C-9), 173.3 (C-O, C-18), 185.5 (C-O, C-5);

MS (m/z) 417.1 [M]⁺; Anal Calcd for C₂₀H₂₀N₂O₈: C, 57.69; H, 4.84; N, 6.73 found C, 57.64; H, 4.75; N, 6.72.

General Procedure for synthesis of compound i of scheme 4.

Into a round bottom flask 1.35 mol of compound (substituted aldehyde) was placed and 0.25 mol of acid

chloride was taken. Weighed out 0.275 mol of powdered, anhydrous aluminium chloride into a dry stoppered

conical flask, and added the solid, with frequent shaking, during 10 min to the contents of the flask, and treated

in microwave. After complete evolution of hydrogen chloride poured the content of the flask while still warm

into a mixture of 200 gm of crushed ice and 100 ml of conc. hydrochloric acid. Filter it and washed with 50 ml

of 5% sodium hydroxide solution, then with water, and dried with calcium chloride.

General Procedure for synthesis of compounds ii and iii of scheme 3.

Page 27 of 37

New Journal of Chemistry

The procedure is similar to that of synthesis of compound i of scheme 1 and 2.

General Procedure for synthesis of compound iv of scheme 3.

View Article Online

DOI: 10.1039/C8NJ02077A

The procedure is similar to that of synthesis of compound ii of scheme 1 and 2.

General Procedure for synthesis of compounds D 1- 9 of scheme 4.

The procedure is similar to that of synthesis of compounds AI1-8 and AII1-8 of scheme 1 and 2.

General Procedure for synthesis of compounds E 1-10 of scheme 4.

The procedure is similar to that of synthesis of compounds Ca 1-8 and Cb 2-5 of scheme 1 and 2.

(Z)-4-{2-[3-(4-ethylphenyl)-3-oxoprop-1-en-1-yl]-5-fluorobenzoyl}phenyl nitrate (D1)

By following above methods, the title compound D1 was obtained as a yellow solid in 64.23 % yield; mp 168-

170 ⁰C; IR (KBr) 782 (C-H aromatic bending), 1119 (C-F stretching), 1584 (O-NO₂), 1630 (C=C alkene), 1680

(C-O chalcone), 1738 (C-O ketone), 3060 (C-H aromatic streching) cm^–1; ¹H NMR (CDCl₃) : 1.19 (t, 3H, J =

8.00 Hz), 2.67 (tdd, 2H, J = 8.00 Hz), 7.00 (m, 1H), 7.28 (m, 2H, J = 7.50 Hz), 7.30 (m, 1H, J = 7.50), 7.34 (m,

13

2H), 7.44 (m, 2H, J = 7.50 Hz), 7.50 (m, 1H), 7.83 (m, 2H, J = 7.50 Hz) 7.85 (m, 2H, J = 7.50 Hz); C NMR

(CDCl₃) : 15.4 (CH₃, C-28), 28.5 (CH₂, C-27), 119.7 (C, C-4), 125.1 (CH=, C-16), 127.6 (CH, C-19), 127.6

(CH, C-20), 128.6 (CH, C-21), 128.6 (CH, C-22), 129.1 (CH, C-11), 129.1 (CH, C-12), 129.7 (CH, C-5), 129.7

(CH, C-9), 129.7 (CH, C-10), 131.3 (C-C. C-1), 131.7 (CH, C-6), 132.3 (CH, C-2), 133.7 (C, C-3), 134.5 (C-C,

C-8), 136.9 (C, C-18), 137.7 (CH=, C-15), 142.5 (C-N, C-13), 146.4 (C, C-23), 191.9 (C-O, C-17), 195.1 (C-O,

C-7); MS (m/z) 420.1 [M]⁺; Anal Calcd for C₂₄H₁₈FNO₅: C, 68.73; H, 4.33; N, 3.34 found C, 68.75; H, 4.31; N,

3.30.

(Z)-4-{5-bromo-2-[3-(4-ethylphenyl)-3-oxoprop-1-en-1-yl]benzoyl}phenyl nitrate (D2)

By following above methods, the title compound D2 was obtained as a yellow solid in 66.01 % yield; mp 156-

158 ⁰C; IR (KBr) 1320, 1640 (C-O chalcone), 1689, 1760, 3180 cm^–1; ¹H NMR (CDCl₃) : 1.19 (t, 3H, J = 8.00

Hz), 2.67 (tdd, 2H), 7.01 (d, 1H, J = 10.90), 7.26 (m, 1H, J = 7.50), 7.28 (m, 2H, J = 7.50 Hz), 7.35 (dd, 1H, J

= 10.90 Hz), 7.43 (dt, 2H, J = 7.50 Hz), 7.82 (dt, 2H, J = 7.50 Hz), 7.85 (m, 2H, J = 7.50 Hz), 7.86 (dt, 1H),

7.97 (d, 1H); ¹³C NMR (CDCl₃) : 15.5 (CH₃, C-28), 28.6 (CH₂, C-27), 119.7 (C-Br, C-4), 125.1 (CH, C-16),

127.6 (CH, C-19), 127.6 (CH, C-20), 128.6 (CH, C-21), 128.6 (CH, C-22), 129.1 (CH, C-11), 129.1 (CH, C-

12), 129.7 (CH, C-5), 129.7 (CH, C-9), 129.7 (CH, C-10), 131.3 (C, C-1), 131.7 (CH, C-6), 132.3 (CH, C-2),

133.7 (C, C-3), 134.5 (C, C-8), 136.9 (C, C-18), 137.7 (CH=, C-15), 142.5 (C-N, C-13), 146.4 (C, C-23), 191.9

(C-O, C-17), 195.1 (C-O, C-7); MS (m/z) 480.3 [M]⁺. Anal Calcd for C₂₄H₁₈BrNO₅: C, 60.02; H, 3.78; N, 2.92

found C, 60.01; H, 3.73; N, 2.90.

(Z)-4-{5-chloro-2-[3-(4-methylphenyl)-3-oxoprop-1-en-1-yl]benzoyl}phenyl nitrate (D3)

By following above methods, the title compound D3 was obtained as a yellow solid in 69.01 % yield; mp 138-

0

1

140 C; IR (KBr) 1074, 1686 (C-O chalcone), 1705, 1764, 2850 cm^–1; H NMR (CDCl₃) : 2.30 (s, 3H), 7.00

(d, 1H, J = 10.90 Hz), 7.28 (m, 2H, J = 7.50 Hz), 7.29 (dt, 1H, J = 10.90), 7.37 (m, 1H, J = 7.50 Hz), 7.38 (ddd,

2H, J = 7.50 Hz), 7.74 (m, 2H), 7.77 (m, 3H, J = 7.50 Hz), 7.80 (m, 1H); ¹³C NMR (CDCl₃) : 21.4 (CH, C-26),

125.1 (CH, C-16), 128.9 (CH, C-5), 128.9 (CH, C-19), 128.9 (CH, C-20), 129.1 (CH, C-11), 129.1 (CH, C-12),

129.3 (CH, C-2), 129.6 (CH, C-21), 129.6 (CH, C-22), 129.7 (CH, C-9), 129.7 (CH, C-10), 131.2 (C, C-1),

New Journal of Chemistry

Page 28 of 37

132.3 (C-Cl, C-4), 132.5 (CH, C-6), 134.1 (C, C-3), 134.4 (C, C-8), 135.0 (C, C-18), 139.1 (CH=, C-15), 142.5

(C-N, C-13), 143.3 (C, C-23), 192.2 (C-O, C-17), 194.7 (C-O, C-7); MS (m/z) 422.0 [M]⁺; Anal Calcd for

View Article Online

DOI: 10.1039/C8NJ02077A

C₂₃H₁₆ClNO₅: C, 65.49; H, 3.82; N, 3.32 found C, 65.46; H, 3.83; N, 3.30.

(Z)-4-{5-methyl-2-[3-(4-nitrophenyl)-3-oxoprop-1-en-1-yl]benzoyl}phenyl nitrate (D4)

By following above methods, the title compound D4 was obtained as a yellow solid in 59.18 % yield; mp 156-

0

158 C; IR (KBr) 740, 1550, 1670 (C-O, chalcone), 1680, 1760, 3320 cm^–1; ¹H NMR (CDCl₃) : 2.30 (s, 3H),

7.03 (d, 1H, J = 10.90 Hz), 7.27 (m, 1H, J = 7.50 Hz), 7.28 (m, 2H, J = 7.50 Hz), 7.38 (m, 1H, J = 10.90 Hz),

13

7.40 (m, 1H), 7.52 (dd, 1H), 7.88 (d, 2H, J = 7.50 Hz), 8.03 (m, 2H, J = 7.50 Hz), 8.34 (m, 2H, J = 7.50); C

NMR (CDCl₃) : 21.1 (CH₃, C-25), 125.1 (CH, C-16), 125.2 (CH, C-21), 125.2 (CH, C-22), 128.7 (CH, C-5),

128.7 (CH, C-6), 129.1 (CH, C-11), 129.1 (CH, C-12), 129.4 (CH, C-2), 129.7 (CH, C-9), 129.7 (CH, C-10),

130.1 (CH, C-19), 130.1 (CH, C-20), 130.2 (C, C-1), 133.0 (C, C-3), 134.2 (C, C-8), 136.2 (C, C-4), 140.3

(CH=, C-15), 142.5 (C-N, C-13), 143.1 (C, C-18), 150.0 (C-N, C-23), 192.3 (C-O, C-17), 194.5 (C-O, C-7);

MS (m/z) 433.1 [M]⁺. Anal Calcd for C₂₃H₁₆N₂O₇: C, 63.89; H, 3.73; N, 6.48 found C, 63.90; H, 3.70; N, 6.50.

(Z)-4-{2-[3-(4-aminophenyl)-3-oxoprop-1-en-1-yl]-5-methylbenzoyl}phenyl nitrate (D5)

By following above methods, the title compound D5 was obtained as a yellow solid in 61.43 % yield; mp 162-

164 ⁰C; IR (KBr) 850, 1020, 1610 (C-O chalcone), 1758, 3140 cm^–1; ¹H NMR (CDCl₃) : 2.30 (s, 5H), 6.73 (m,

2H, J = 7.50 Hz), 7.03 (d, 1H, J = 10.90 Hz), 7.27 (m, 1H, J = 7.50 Hz), 7.28 (m, 2H, J = 7.50 Hz), 7.38 (m, 1H,

J = 10.90 Hz), 7.40 (m, 1H), 7.44 (m, 2H, J = 7.50 Hz), 7.52 (dd, 1H, J = 7.50 Hz), 7.88 (m, 2H, J = 7.50 Hz);

¹³C NMR (CDCl₃) : 21.1 (CH₃, C-25), 114.2 (CH, C-21), 114.2 (CH, C-22), 125.1 (CH, C-16), 128.7 (CH, C-

5), 128.7 (CH, C-6), 129.1 (CH, C-11), 129.1 (CH, C-12), 129.4 (CH, C-2), 129.7 (CH, C-9), 129.7 (CH, C-

10), 131.2 (C, C-18), 132.0 (CH, C-19), 132.0 (CH, C-20), 133.0 (C, C-3), 134.2 (C, C-8), 136.2 (C, C-4),

139.4 (C, C-1), 140.3 (CH, C-15), 142.5 (C-N, C-13), 155.0 (C-N, C-23), 192.4 (C-O, C-17), 194.5 (C-O, C-7);

MS (m/z) 403.1 [M]⁺. Anal Calcd for C₂₃H₁₈N₂O₅: C, 68.65; H, 4.51; N, 6.96 found C, 68.61; H, 4.50; N, 6.92.

(Z)-4-{5-methyl-2-[3-(3-nitrophenyl)-3-oxoprop-1-en-1-yl]benzoyl}phenyl nitrate (D6)

By following above methods, the title compound D6 was obtained as a yellow solid in 61.03 % yield; mp 162-

0

164 C; IR (KBr) 820, 1120, 1630 (C-O chalcone), 1680 (C-O ketone), 1780, 3180 cm^–1; ¹H NMR (CDCl₃) :

2.30 (s, 3H), 7.01 (d, 1H, J = 10.90 Hz), 7.26 (m, 1H, J = 10.90 Hz), 7.28 (m, 2H, J = 7.50 Hz), 7.43 (m, 2H, J

= 7.50 Hz), 7.53 (q, 1H), 7.68 (m, 1H), 7.72 (m, 2H, J = 7.50 Hz), 8.40 (ddt, 2H, J = 7.50 Hz), 8.61 (m, 1H);

¹³C NMR (CDCl₃) : 21.1 (CH₃, C-25), 123.2 (CH, C-20), 125.1 (=CH, C-16), 127.2 (CH, C-23), 128.7 (CH,

C-5), 128.7 (CH, C-6), 129.1 (CH, C-11), 129.1 (CH, C-12), 129.4 (CH, C-2), 129.7 (CH, C-9), 129.7 (CH, C-

10), 130.6 (CH, C-21), 133.0 (C, C-3), 134.1 (CH, C-19), 134.2 (C, C-8), 136.2 (C, C-4), 139.4 (C, C-1), 139.8

(C, C-18), 141.2 (CH=, C-15), 142.5 (C-N, C-13), 148.5 (C-N, C-22), 191.7 (C-O, C-17), 194.5 (C-O, C-7);

MS (m/z) 433.1 [M]⁺; Anal Calcd for C₂₃H₁₆N₂O₇: C, 63.89; H, 3.73; N, 6.48. found C, 63.90; H, 3.71; N, 6.42.

(Z)-4-(2-{3-[3,4-(dihydroxymethyl)phenyl]-3-oxoprop-1-en-1-yl}-5-methylbenzoyl)phenyl nitrate (D7)

By following above methods, the title compound D7 was obtained as a yellow solid in 64.91 % yield; mp 170-

0

1

172 C; IR (KBr) 780, 1024, 1675 (C-O chalcone), 1725, 1774, 2950 cm^–1; H NMR (CDCl₃) : 2.30 (s, 5H),

4.80 (d, 4H), 6.98 (d, 1H, J = 10.90 Hz), 7.26 (m, 1H), 7.28 (m, 2H, J = 10.90 Hz), 7.43 (s, 2H, J = 7.50 Hz),

Page 29 of 37

New Journal of Chemistry

7.48 (dd, 1H, J = 7.50 Hz), 7.53 (q, 1H), 7.72 (m, 2H, J = 7.50 Hz), 7.74 (m, 1H), 7.85 (dd, 1H, J = 7.50 Hz);

¹³C NMR (CDCl₃) : 21.6 (CH, C-25), 62.61 (CH₂, C-28), 62.79 (CH₂, C-27), 123.2 (CH₂, C-12), 125.1 (CH,

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C-16), 128.2 (CH, C-11), 128.7 (CH, C-19), 128.7 (CH, C-20), 129.1 (CH, C-5), 129.1 (CH, C-6), 129.4 (CH,

DOI: 10.1039/C8NJ02077A

C-21), 129.7 (CH, C-9), 129.7 (CH, C-10), 133.0 (C, C-3), 134.1 (CH, C-2), 134.2 (C, C-8), 136.1 (C, C-4),

138.0 (CH, C-23), 138.5 (CH, C-22), 139.5 (C, C-1), 139.8 (C, C-18), 141.3 (CH=, C-15), 142.5 (C-N, C-13),

192.1 (C-O, C-17), 194.4 (C-O, C-7); MS (m/z) 448.1 [M]⁺; Anal Calcd for C₂₅H₂₁NO₇: C, 67.11; H, 4.73; N,

3.13 found C, 67.14; H, 4.70; N, 3.14.

(Z)-4-{2-[3-(4-chlorophenyl)-3-oxoprop-1-en-1-yl]-5-methylbenzoyl}phenyl nitrate (D8)

By following above methods, the title compound D8 was obtained as a yellow solid in 56.05 % yield; mp 150-

0

152 C; IR (KBr) 765, 1050, 1630 (C-O chalcone), 1680 (C-O ketone), 1760, 3210 cm^–1; ¹H NMR (CDCl₃) :

2.30 (s, 3H), 6.98 (d, 1H, J = 10.90 Hz), 7.28 (m, 3H, J = 7.50, 10.90 Hz), 7.41 (m, 1H, J = 7.50 Hz), 7.43 (m,

13

1H), 7.51 (m, 2H, J = 7.50 Hz), 7.53 (m, 1H), 7.74 (m, 2H, J = 7.50 Hz), 7.80 (m, 2H, J = 7.50 Hz); C NMR

(CDCl₃) : 21.1 (CH₃, C-25), 125.1 (=CH-, C-16), 128.7 (CH, C-5), 128.7 (CH, C-6), 129.1 (CH, C-11), 129.1

(CH, C-12), 129.4 (CH, C-2), 129.5 (CH, C-19), 129.5 (CH, C-20), 129.7 (CH, C-9), 129.7 (CH, C-10), 129.7

(CH, C-21), 129.7 (CH, C-22), 133.0 (C, C-3), 134.2 (C, C-8), 136.2 (C, C-4), 139.1 (C-Cl, C-23), 139.4 (C, C-

1), 140.5 (C, C-18), 142.0 (CH=, C-15), 142.5 (C-N, C-13), 192.0 (C-O, C-17), 194.5 (C-O, C-7); MS (m/z)

422.0 [M]⁺; Anal Calcd for C₂₃H₁₆ClNO₅: C, 65.49; H, 3.82; N, 3.12 found C, 65.45; H, 3.80; N, 3.14.

(Z)-4-{5-methyl-2-[3-(4-ethylphenyl)--3-oxo-3-phenylprop-1-en-1-yl]benzoyl}phenyl nitrate (D9)

By following above methods, the title compound D9 was obtained as a yellow solid in 67.05 % yield; mp 146-

0

148 C; IR (KBr) 762, 1070, 1644 (C-O chalcone), 1690 (C-O ketone), 1760, 3200 cm^–1; ¹H NMR (CDCl₃) :

1.19 (t, 3H, J = 8.00 Hz), 2.30 (s, 5H), 2.67 (dt, 2H, J = 8.00 Hz), 6.98 (d, 1H, J = 10.90 Hz), 7.26 (m, 1H, J =

7.50 Hz), 7.28 (m, 2H, J = 7.50 Hz), 7.31 (d, 1H, J = 10.90 Hz), 7.38 (ddd, 1H, J = 7.50 Hz), 7.44 (m, 2H, J =

7.50 Hz), 7.49 (dd, 1H), 7.83 (m, 2H, J = 7.50 Hz), 7.86 (m, 2H, J = 7.50 Hz); ¹³C NMR (CDCl₃) : 15.5 (CH₃,

C-28), 21.1 (CH₃, C-25), 28.6 (CH₂, C-27), 125.1 (=CH-, C-16), 127.6 (CH, C-19), 127.6 (CH, C-20), 128.6

(CH, C-21), 128.6 (CH, C-22), 128.7 (CH, C-5), 128.7 (CH, C-6), 129.1 (CH, C-11), 129.1 (CH, C-12), 129.4

(CH, C-2), 129.7 (CH, C-9), 129.7 (CH, C-10), 133.0 (C, C-3), 134.2 (C, C-8), 136.2 (C, C-4), 136.8 (C, C-

18), 139.4 (C, C-1), 142.0 (-CH=, C-15), 142.5 (C-N, C-13), 146.4 (C, C-23), 192.2 (C-O, C-17), 194.5 (C-O,

C-7); MS (m/z) 416.1 [M]⁺; Anal Calcd for C₂₅H₂₁NO₅: C, 72.28; H, 5.10; N, 3.37 found C, 72.24; H, 5.12; N,

3.34.

(Z)-2-oxo-2-[(4-{2-[3-(2-benzoyl-4-nitrophenyl)-1-(4-ethylphenyl)prop-1-enyl]benzoyl}phenyl)amino]

ethyl nitrate (E1)

By following above methods, the title compound E1 was obtained as a yellow solid in 67.09 % yield; mp 134-

136 ⁰C; IR (KBr) 1075, 1360, 1678 (C-O chalcone), 1701, 1730, 2972 cm^–1; ¹H NMR (CDCl₃) : 1.12 (t, 1H),

1.19 (t, 3H, J = 8.00 Hz), 2.35 (q, 2H, J = 8.00 Hz), 2.67 (tdd, 2H, J = 8.00 Hz), 7.04 (d, 1H, J = 10.90 Hz), 7.23

(m, 2H, J = 10.90 Hz), 7.27 (m, 1H), 7.46 (dt, 2H, J = 7.50 Hz), 7.56 (dd, 1H, J = 7.50 Hz), 7.86 (dd, 2H, J =

7.50 Hz), 7.90 (m, 2H, J = 7.50 Hz), 8.46 (dd, 1H, J = 7.50 Hz), 8.75 (d, 1H, J = 7.50 Hz); ¹³C NMR (CDCl₃) :

15.5 (CH₃, C-34), 27.6 (CH₂, C-27), 28.6 (CH₂, C-32), 119.4 (CH, C-11), 119.4 (CH, C-12), 125.1 (=CH-, C-

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DOI: 10.1039/c8nj02077a

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