Synthesis of 3-N-Sugar-substituted-2,4(1H, 3H)-quinazolinediones as anti-angiogenesis agents

Article abstract of DOI:10.3390/molecules14072447

A series of novel 3-N-sugar-substituted quinazolinediones were synthesized through the cyclization of the intermediate 2-aminobenzamides using triphosgene as the condensing reagent. Their anti-angiogenesis activities were investigated. The compound 3-(2'-

Full text of DOI:10.3390/molecules14072447

Molecules 2009, 14, 2447-2457; doi:10.3390/molecules14072447
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molecules
ISSN 1420-3049
www.mdpi.com/journal/molecules
Article
Synthesis of 3-N-Sugar-substituted-2, 4(1H, 3H)-
quinazolinediones as Anti-Angiogenesis Agents
Conghai Huang, Xiangbao Meng, Jingrong Cui and Zhongjun Li *
State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking
University, Beijing 100191, China; E-mails: michaelhchh@gmail.com (C.H.),
xbmeng@bjmu.edu.cn (X.M.), jrcui@bjmu.edu.cn (J.C.)
* Author to whom correspondence should be addressed; E-mail: zjli@bjmu.edu.cn (Z.L);
Tel.:+86-10-82801714; Fax: 86-10-82805496
Received: 8 May 2009; in revised form: 27 May 2009 / Accepted: 2 June 2009 /
Published: 8 July 2009
Abstract: A series of novel 3-N-sugar-substituted quinazolinediones were synthesized
through the cyclization of the intermediate 2-aminobenzamides using triphosgene as the
condensing reagent. Their anti-angiogenesis activities were investigated. The compound 3-
(2'-aminoglucosyl)-2,4-(1H,3H)-quinazolinedione, (5d) showed good anti-angiogenesis
activity.
Keywords: quinazolinediones; anti-angiogenesis; triphosgene
1. Introduction
The development of an effective anti-cancer drug is still a major challenge in the field of drug
discovery. It was reported that aminopeptidase N (APN) plays a crucial role in the degradation and
invasion of extracellular matrices by fibrosarcoma cells [1]. It is also important in the proliferation and
the activation of pathogenic T-cells [2]. Several APN inhibitors were prepared to treat inflammatory
disease, autoimmune disease, allogenic rejection reactions and allergies. In addition, APN antagonists
were found to specifically inhibit angiogenesis in chorioallantoic membranes and in the retina, thus
suppressing tumor growth. Therefore, APN was believed to be involved in angiogenesis and can serve
as a target for the development of anti-cancer drugs [3-5].

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The quinazolinediones have inhibitory activities towards some amino peptidases, such as
puromycin-sensitive aminopeptidase (PSA) [5] and aminopeptidase N [1]. One representative
compound, PAQ-22 (Figure 1), showed potent and specific PSA inhibiting activity with an IC50 of
0.09 μg/mL [5]. The inhibitory mechanism of these compounds was through non-competition, as
revealed by the Lineweaver-Burk plot analysis. Structure-activity relationship studies indicated that
tautomerism of the imidobenzoylketone group of the cyclic imide moiety of these kinds of inhibitors
was important for the inhibitory activity [5].
Figure 1. Structures of PAQ-22 and the desired 3-N-sugar substituted quinazolinedione
derivatives.
It is reported that glucosamine, a type of amino-sugar, possesses immunosuppressive activity and
could be beneficial as an immunosuppressive agent [6-7]. Water-soluble conjugates of glucosamine
and glucosamine 6-sulfate were reported showing immunomodulatory and anti-angiogenesis properties,
These derivatives of glucosamine could function synergistically to prevent scar tissue
formation [8-10].
To find novel anti-angiogenesis agents, we have synthesized a series of 3-N-sugar-substituted-2,4-
(1H,3H)-quinazolinediones containing amino-sugar moieties.
2. Results and Discussion
Generally 3-N-substituted-2,4-(1H,3H)-quinazolinediones could be synthesized through different
intermediates, including 2-amino benzamide [11], 2-ureayl benzoic ester [12-14], 2-isocyanato
benzoate [15-16] and others [17-18]. Considering the known instability of quinazolinediones and the
glucosamine moiety under acidic conditions, 2-amino-(N-sugar-substituted) benzamides were chosen
as the key intermediates and a mild condensation condition was adopted in the synthetic route. During
the synthesis of sugar-N3-substituted quinazolinediones, the unprotected aminosugar was used in the
preparations of 2-amino-(N-sugar-substituted) benzamides. The aminosugars were prepared by the
reported method [19]. The general synthesis of the key 2-nitro-(N-sugar-substituted) benzamide
intermediates was readily performed by the condensation of 2-nitrobenzoic acid and unprotected
aminosugars with EDC(DCC)/HOBt [20-21] (Scheme 1). After formation of amides, the sugar
hydroxyl groups were fully acetyled by Ac2O/pyridine at room temperature, and then the nitro group
was smoothly reduced by powdered Zn in acetic acid/THF. Finally, cyclization with triphosgene in
CH2Cl2 (or ClCH2CH2Cl) was performed to produce the target molecules [20-21].

Molecules 2009, 14
Scheme 1. The synthetic route to N-sugar-substituted quinazolinedione derivatives.
2449
To prepare the intermediate 2-nitro-(N-sugar-substituted) benzamides from aminosugars,
condensations of protected amino-sugars with 2-nitrobenzoyl chloride or with 2-nitrobenzoic acid
activated by DCC (or EDC/HOBt) were attempted, but all these efforts failed. It was reported that the
unprotected amino-sugars could be used directly to synthesize related amides [20-21], and following
this method, the key N-sugar o-nitrobenzamide intermediates were obtained with isolated yields
of 40-47%.
The N-sugar-substituted-2,4-(1H,3H)-quinazolinediones 5a-d were obtained from the 2-amino-
benzamides by carbonylation cyclization with carbonyldiimidazole (CDI), triphosgene and ethyl
chlorocarbonate [20-21]. Several condensation conditions were tested. The results showed in Table 1
indicated that triphosgene had a higher activity than CDI and ethyl chlorocarbonate (Scheme 2).
Therefore, triphosgene was used as the condensation reagent. After deacetylation with NaOMe/
MeOH, the target compounds 6a-d were obtained in about 20% total yields.
Table 1. Optimization of the conditions for the preparation of sugar-substituted
quinazolinedine derivatives.
Entry Reactant Product
Reagent
Solvent
Reflux
Time (h)
48
Isolated
Yield (%)
N.R b
1
2
3
4a
4a
4a
5a
5a
5a
CDI a
CDI a
THF
ClCH2CH2Cl
CH2Cl2
48
12
N.R b
triphosgene
89%

Molecules 2009, 14
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Table 1. Cont.
4
5
6
7
8
4a
5a
5b
5b
5b
5b
triphosgene ClCH2CH2Cl
6
85%
N.R b
N.R b
84%
4b
4b
4b
4b
CDI a
THF
48
48
12
8
ClCO2Et
triphosgene
CH3CN
CH2Cl2
triphosgene ClCH2CH2Cl
88%
a CDI: carbonyldiimidazole; b N.R: no reaction.
The obtained N-sugar substituted-2,4-(1H,3H)-quinazolinediones 5a-d and 6a-d were primarily
assayed for their angiogenesis inhibition activity using the chick chorioallantoic membrane (CAM)
model [22]. Only compound 5d showed good inhibitory activity to the neovascularization of chick in
vivo (Figure 2).
Figure 2. Inbibition of angiogenesis by compound 5d.
3. Experimental
3.1. Instruments and apparatus
1H- and 13C-NMR spectra were recorded on a Varian VXR 300 MHz spectrometer with Me4Si as
the internal standard and CDCl3 or Me2SO-d6 as solvent. Optical rotations were measured at 25 ºC with
an AA-10R polarimeter. The progress of reactions was monitored by silica-gel GF254 TLC plates.
Detection was performed by examination under UV light and by 15% H2SO4 in EtOH. Preparative
TLC was performed on silica-gel GF254 plates and column chromatography was on silica-gel H. The
inhibitory activity of anti-angiogenesic was assayed under chick chorioallantoic membrances (CAM)
model, monitored by biological dissection microscope of DM-1 and recorded with a NIKON S610
digital camera.
3.2. Preparation of 3-N-sugar-substituted-2,4-(1H,3H)-quinazolinediones
3.2.1. Synthesis and Spectral Data of 2a-c
Aminosugar 1a-c (2.9 g, 15 mmol), o-nitrobenzoic acid (3.2 g, 16.5 mmol) and 1-hydroxy
benzotriazole (HOBt) (4.9 g, 36.3 mmol) were dissolved in DMF (80 mL). The mixture was cooled to
0 ºC and stirred for 30 min. Then a solution of dicyclohexylcarbodiimide (DCC, 3.8 g, 18.2 mmol) in

Molecules 2009, 14
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DMF (15 mL) was added dropwise. The mixture was stirred for 18 h at room temperature and filtered.
The filtrate was evaporated to dryness under reduced pressure, and the residue was purified by column
chromatography on silica gel to give 2a-c.
Methyl-6-(o-nitro)benzamidyl-6-deoxy-α-D-glucopyranoside (2a). White flocculant crystals; Yield:
47.0%; mp: 230-233 ºC; []D +116o (c 1.01, MeOH); 1H-NMR δ (ppm) (DMSO-d6): 3.18 (m, 1H, H-
6b), 3.34 (m, 1H, H-2), 3.38 (s, 3H, OCH3), 3.47 (m, 2H, H-4,5), 3.61 (m, 1H, H-3), 3.85 (m, 1H, H-5),
4.51 (d, 1H, J1, 2 1.2Hz, H-1), 4.67 (d, 1H, J 6.0 Hz, H-OH), 4.79 (d, 1H, J 5.1 Hz, H-OH), 4.94 (d, 1H,
J 5.4 Hz, H-OH), 7.55-8.03 (m, 4H, Ph), 8.76 (t, 1H, J5.1Hz, H-NH); 13C-NMR δ (ppm) (DMSO-d6):
40.8 (C-6), 54.4 (OCH3), 70.3 (C-5), 71.9 (C-3), 72.3 (C-2), 73.0 (C-4), 99.7 (C-1), 124.0 (Ph), 129.1
(Ph), 130.6 (Ph), 132.6 (Ph), 133.5 (Ph) , 147.1 (Ph), 165.1 (C=O); ESI-TOF-MS: [M+1]+ m/z 343.0;
[M+Na]+ m/z 365.0.
Methyl-6-(o-nitro)benzamidyl-6-deoxy-α-D-galactopyranoside (2b). White flocculant crystals; Yield:
1
42.3%; mp: 218- 220 ºC; []D +52o (c 1.01, DMSO); H-NMR δ (ppm) (DMSO-d6): 3.28 (s, 3H,
OCH3), 3.01-3.77 (m, 5H, sugar-H), 4.57 (m, 3H, sugar-H), 7.57-8.03 (m, 4H, Ph), 8.82 (d, 1H, H-
NH); 13C-NMR δ (ppm) (DMSO-d6): 45.5 (C-6), 54.6 (OCH3), 68.3 (C-2), 68.4 (C-5), 69.3 (C-4), 69.4
(C-3), 100.2 (C-1), 124.0 (Ph), 129.0 (Ph), 130.7 (Ph), 132.4 (Ph), 133.5 (Ph), 147.1 (Ph), 165.7
(C=O); ESI-TOF-MS: [M+1]+ m/z 343.0; [M+Na]+ m/z 365.0.
Methyl-6-(o-nitro)benzamidyl-6-deoxy-α-D-mannopyranoside (2c). White flocculant crystals; Yield:
47.0%; mp: 188-189 ºC; []D +56o (c 1.01, CHCl3); 1H-NMR δ (ppm) (DMSO-d6): 3.13-3.49 (m, 5H,
H-sugar), 3.39 (s, 3H, OCH3), 4.60 (m, 1H, H-sugar), 4.50 (s, 1H, H-1), 4.77 (d, J 8.7 Hz, H-OH),
4.78(d, J 4.8 Hz, H-OH), 4.92 (d, J 5.4 Hz, H-OH), 7.54-8.03 (m, 4H, Ph), 8.76 (t, 1H, J 5.1 Hz, H-
NH); 13C-NMR δ (ppm) (DMSO-d6): 41.0 (C-6), 54.1 (OCH3), 69.6 (C-4), 70.2 (C-5), 70.6 (C-3), 71.4
(C-2), 101.0 (C-1), 124.0 (Ph), 129.1 (Ph), 130.6 (Ph), 132.6 (Ph), 133.5 (Ph), 147.1 (Ph), 165.9
(C=O); ESI-TOF-MS: [M+1]+ m/z 343.0; [M+Na]+ m/z 365.0.
3.2.2. Synthesis and Spectral Data of 2-(o-nitro)benzamidyl-2-deoxy-β-D-glucopyranose (2d)
Glucosamine hydrochloride (7.8 g, 36 mmol) and sodium methoxide (2.25 g, 41.7 mmol) were
added to methanol (100 mL). The mixture was stirred for 20 min and then evaporated to dryness under
vacuum. The residue was dissolved in DMF (200 mL), followed by the addition of o-nitrobenzoic acid
(5.1 g, 30 mmol) and 1-hydroxybenzotriazole (HOBt, 9.5 g, 72 mmol). The mixture was cooled to 0 ºC
and stirred for 30 min. Then the solution of dicyclohexylcarbodiimide (DCC, 6.9 g, 36 mmol) in DMF
(25 mL) was added dropwise. The mixture was stirred for 20 h at room temperature and filtered. The
filtrate was evaporated to dryness under reduced pressure, and the residue was purified through
column chromatography on silica gel to yield 5.5 g of white flocculant crystals of 2d; yield: 47%; mp:
1
208-212 ºC; []D +40o (c 1.01, MeOH); H-NMR δ (ppm) (DMSO-d6): 3.28 (m, 1 H, H-sugar), 3.43-
3.83 (m, 5 H, H-sugar), 4.55 (t, 1H, J 5.7 Hz, H-OH), 4.80 (d, 1H, J5.4Hz, H-OH), 5.05 (d, 1H, J 5.4
Hz, H-OH),5.18 (s, 1H, H-1), 6.62 (d, 1H, J 4.2 Hz H-OH), 7.73-8.10 (m, 4H, Ph), 8.64(d, 1H, J 8.1
Hz, H-NH); 13C-NMR δ(ppm) (75MHz, DMSO-d6): 55.1, 61.1, 70.1, 71.1, 72.1 (C of sugar ring), 90.4

Molecules 2009, 14
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(C-1), 123.8 (Ph), 129.5 (Ph), 130.6 (Ph), 132.4 (Ph), 133.1 (Ph), 147.3(Ph), 165.5(C=O); ESI-TOF-
MS: [M+1]+ m/z 329.0; [M+Na]+ m/z 351.0.
3.2.3. Synthesis and Spectral Data of 3a-d
The appropriate 2-nitro-(N-sugar-substituted) benzamide 2a-d (2.0 g) was dissolved in pyridine (50
mL), followed by the addition of acetic anhydride (25 mL). The solution was stirred at room
temperature overnight and evaporated to dryness under reduced pressure. The residue was dissolved in
ethyl acetate and washed sequentially with saturated sodium hydrogen carbonate solution, saturated
brine and water. The organic layer was dried over anhydrous Na2SO4 and evaporated under reduced
pressure to give 3a-d as yellow solids.
Methyl-6-(o-nitro-)benzamidyl-6-deoxy-2,3,4-tri-O-acetyl-α-D-glucopyranoside (3a). Yield: 95.0 %;
o
1
mp: 77-79 oC; []D +104 (c 1.01, CHCl3); H-NMR δ (ppm) (CDCl3): 2.02 (s, 3H, Ac), 2.08 (s, 3H,
Ac), 2.10 (s, 3H, Ac), 3.42 (s, 3H, OCH3), 3.61 (m, 1H, H-6), 3.79 (m, 1H, H-5), 4.04 (m, 1H, H-5),
4.83 (dd, 1H, J1,2 3.6 Hz, J2,3 10.2 Hz, H-2), 4.91 (d, 1H, J1, 2 3.6 Hz, H-1), 5.02 (t, 1H, J 9.9 Hz, H-3),
13
5.48 (t, 1H, J 9.9 Hz, H-4), 6.26 (t, 1H, J 5.7 Hz, H-NH), 7.27-8.09 (m, 4H, Ph); C-NMR δ (ppm)
(CDCl3): 20.7 (CH3CO), 39.4 (C-6), 55.0 (OCH3), 67.6 (C-5), 69.2 (C-3), 69.8 (C-2), 70.9 (C-4), 96.8
(C-1), 124.5 (Ph), 129.0 (Ph), 130.5 (Ph), 132.7 (Ph), 133.9 (Ph), 146.2 (Ph), 166.6 (C=O), 169.9
(CH3CO), 170.2 (CH3CO), 170.3 (CH3CO); ESI-TOF-MS: [M+1]+ m/z 469.1; [M+Na]+ m/z 491.1.
Methyl-6-(o-nitro-)benzamidyl-6-deoxy-2,3,4-tri-O-acetyl-α-D-galactopyranoside (3b). Yield: 98.0%;
1
mp: 87-90 ºC; []D+68o (c 1.01, CHCl3); H-NMR δ (ppm) (CDCl3): 1.99 (s, 3H, Ac), 2.07 (s, 3H,
Ac), 2.18 (s, 3H, Ac), 3.42(s, 3H, OCH3), 3.54 (m, 2H, H-6), 4.22 (t, 1H, J 6.6 Hz, H-5), 4.98 (d, 1H,
J1, 2 3.0 Hz, H-1), 5.16 (dd, 1H, J1,2 3.0 Hz, J2,3 10.8 Hz, H-2), 5.37-5.46 (m, 2H, H-4, H-3), 6.42 (br,
13
1H, H-NH), 7.38-8.06 (m, 4H, Ph); C-NMR δ (ppm) (CDCl3): 20.6 (CH3CO), 20.7 (CH3CO), 20.8
(CH3CO), 39.3 (C-6), 55.7 (OCH3), 66.5 (C-5), 67.4 (C-3), 68.2 (C-2), 69.0 (C-4), 97.2 (C-1), 124.5
(Ph), 128.6 (Ph), 130.6 (Ph), 132.5 (Ph), 133.8 (Ph), 146.4 (Ph), 166.6 (C=O), 169.7 (CH3CO), 170.4
(CH3CO), 170.8 (CH3CO); ESI-TOF-MS: [M+Na]+ m/z 491.0.
Methyl-6-(o-nitro-)benzamidyl-6-deoxy-2,3,4-tri-O-acetyl-α-D-mannopyranoside (3c). Yield: 91.3%;
1
mp:162-164 ºC; []D+28o (c 1.10, CHCl3); H-NMR δ (ppm) (CDCl3): 2.00 (s, 3H, Ac), 2.11 (s, 3H,
Ac), 2.14 (s, 3H, Ac), 3.38 (s, 3H, OCH3), 3.60 (m, 1H, H-6e), 3.78 (m, 2H, H-6a, 5), 4.67 (s, 1H, H-
13
1), 5.20-5.34 (m, 3H, H-2, 3, 4), 6.40 (t, 1H, J 6.6 Hz, H-NH), 7.58-8.09 (m, 4H, Ph); C-NMR δ
(ppm) (CDCl3): 20.7(CH3CO), 20.8 (CH3CO), 39.8 (C-6), 55.3 (OCH3), 66.8 (C-4), 68.8 (C-5), 68.9
(C-3), 69.6 (C-2), 98.5 (C-1), 124.6 (Ph), 128.7 (Ph), 130.6 (Ph), 132.9 (Ph), 133.7 (Ph), 146.3(Ph),
166.4(C=O), 169.8 (CH3CO), 169.9 (CH3CO), 170.4 (CH3CO); ESI-TOF-MS: [M+1]+ m/z 469.0;
[M+Na]+ m/z 491.0.
2-(o-Nitro)benzamidyl-2-deoxy-1,3,4,6-tetra-O-acetyl-β-D-glucopyranose (3d). Yield: 93.0%; mp:
144-148 ºC; []D +40o (c 1.01, CHCl3); 1H-NMR δ (ppm) (CDCl3): 2.06 (s, 3H, Ac), 2.11 (s, 3H, Ac),
2.14 (s, 3H, Ac), 2.17 (s, 3H, Ac), 4.05-4.13 (m, 2H, H-6), 4.30 (dd, 1H, J 3.6 Hz, 12.6 Hz, H-4), 4.67
(m, 1H, H-5), 5.30 (m, 2H, H-2,3), 6.14 (d, 1H, J 8.4 Hz, H-1), 6.40 (d, 1H, J 3.6 Hz, H-NH), 7.27-

Molecules 2009, 14
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8.09 (m, 4H, Ph);13C-NMR δ (ppm) (CDCl3): 20.5 (CH3CO), 20.7 (CH3CO), 20.8 (CH3CO), 20.9
(CH3CO), 51.9 (OCH3), 61.4 (C-sugar), 67.4 (C-sugar), 69.8 (C-sugar), 70.0 (C-sugar), 90.4(C-1),
124.6 (Ph), 128.7 (Ph), 130.8 (Ph), 132.0 (Ph), 134.0 (Ph), 145.9 (Ph), 166.5 (C=O), 168.7 (CH3CO),
169.9 (CH3CO), 170.7 (CH3CO), 172.4 (CH3CO); ESI-TOF-MS: [M+Na]+ m/z 519.1.
3.2.4. Synthesis and Spectral Data of 4a-c
The appropriate compound 3a-c (2.0 g, 7.4 mmol) was dissolved in THF (50 mL) and acetic acid
(5 mL). Under stirring, zinc power (1.3 g, 20 mmol) was added slowly. The mixture was then refluxed
for 2 h, cooled to room temperature, and filtered through a short column of silica gel. The eluent was
evaporated to dryness under vacuum. The residue was dissolved in ethyl acetate and washed
sequentially with saturated sodium hydrogen carbonate solution, saturated brine and water. The
organic layer was dried over anhydrous Na2SO4 and evaporated under reduced pressure to afford the
compounds 4a-c as yellow solids.
Methyl-6-(o-amino)benzamidyl-6-deoxy-2,3,4-tri-O-acetyl-α-D-glucopyranoside (4a). Yield: 88.0%;
mp: 108-110 ºC; []D +98o (c 1.01, CHCl3); 1H-NMR δ (ppm) (CDCl3): 2.01 (s, 3H, Ac), 2.07 (s, 3H,
Ac), 2.09 (s, 3H, Ac), 3.43 (s, 3H, OCH3), 3.61 (m, 1H, H-6), 3.79 (m, 1H, H-5), 4.04 (m, 1H, H-6),
4.83 (dd, 1H, J1,2 3.6 Hz, J2,3 9.6 Hz, H-2), 4.93 (m, 2H, H-1, 3), 5.50 (t, 1H, J 9.6 Hz, H-3), 5.48 (t,
13
1H, J 9.9 Hz, H-4), 6.45 (t, 1H, H-NH), 6.45-7.36 (m, 4H, Ph); C-NMR δ (ppm) (CDCl3): 20.7
(CH3CO), 22.6 (CH3CO), 38.9 (C-6), 55.4 (OCH3), 67.7 (C-5), 69.7 (C-3), 69.9 (C-2), 70.9 (C-4), 96.6
(C-1), 112.2 (Ph), 114.1 (Ph), 127.4 (Ph), 132.9 (Ph), 148.8 (Ph), 169.7 (C=O), 170.0 (CH3CO), 170.1
(CH3CO), 170.2 (CH3CO); ESI-TOF-MS: [M+1]+ m/z 439.1; [M+Na]+ m/z 461.1.
Methyl-6-(o-amino)benzamidyl-6-deoxy-2,3,4-tri-O-acetyl-α-D-galactopyranoside (4b). Yield: 78.0%;
1
mp: 78-80 ºC; []D +28o (c 1.01, CHCl3); H-NMR δ (ppm) (CDCl3): 2.00 (s, 3H, Ac), 2.10 (s, 3H,
Ac), 2.20 (s, 3H, Ac), 3.39 (s, 3H, OCH3), 3.44 (t, 1H, J 6.6 Hz, H-5), 3.60 (dd, 1H, J5,6e 6.9 Hz, J6a,6e
13.5 Hz, H-6e), 4.15 (dd, 1H, J5,6a 6.9 Hz, J6a, 6e 13.5 Hz, H-6a), 5.00 (d, 1H, J1, 2 3.6 Hz, H-1), 5.18
(dd, 1H, J1,2 3.6 Hz, J2,3 10.8 Hz, H-2), 5.37 (dd, 1H, J3,4 3.3 Hz, J2,3 10.8 Hz, H-3), 5.45 (d, 1H, J 3.3
13
Hz, H-4), 6.49 (t, 1H, J 6.3 Hz, H-NH), 6.63-7.33 (m, 4H, Ph); C-NMR δ (ppm) (CDCl3): 20.6
(CH3CO),20.7 (CH3CO), 20.8 (CH3CO), 38.8 (C-6), 55.0 (OCH3), 66.7 (C-5), 67.5 (C-3), 68.3 (C-2),
69.4 (C-4), 97.2 (C-1), 115.2 (Ph), 116.7 (Ph), 117.4 (Ph), 127.0 (Ph), 132.5 (Ph), 148.9 (Ph), 169.2
(C=O), 169.8 (CH3CO) , 170.5 (CH3CO), 171.0 (CH3CO); ESI-TOF-MS: [M+1]+ m/z 439.1; [M+Na]+
m/z 461.1.
Methyl-6-(o-amino)benzamidyl-6-deoxy-2,3,4-tri-O-acetyl-α-D-mannopyranoside (4c). Yield: 77.6%;
mp: 150-154 ºC; []D +40o (c 1.10, CHCl3); 1H-NMR δ (ppm) (CDCl3): 2.00 (s, 3H, Ac), 2.10 (s, 3H,
Ac), 2.12 (s, 3H, Ac), 3.37 (s, 3H, OCH3), 3.40 (m, 1H, H-6e), 3.85-3.98 (m, 2H, H-5, 6a), 4.70 (s, 1H,
H-1), 5.19-5.25 (m, 2H, H-2, 4), 5.36 (dd, 1H, J3,2 3.3 Hz, J3,4 10.8 Hz, H-3), 6.56 (t, 1H, J 5.4 Hz, H-
13
NH), 6.63-7.37 (m, 4H, Ph); C-NMR δ (ppm) (CDCl3): 20.7 (CH3CO), 20.8 (CH3CO), 39.3 (C-6),
55.3 (OCH3), 67.1 (C-4), 68.8 (C-5), 68.9 (C-3), 69.6 (C-2), 98.4 (C-1), 115.8 (Ph), 116.5 (Ph), 117.3
(Ph), 126.9 (Ph), 132.4 (Ph), 148.8 (Ph), 169.2(C=O), 169.9 (CH3CO), 170.0 (CH3CO), 170.3
(CH3CO); ESI-TOF-MS: [M+1]+ m/z 439.1; [M+Na]+ m/z 461.1.

Molecules 2009, 14
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3.2.5. Synthesis and Spectral Data of 4d
Compound 3d (200 mg, 0.4 mmol) was dissolved in methanol (30 mL), and 40% Pd(OH)2 (20 mg)
was added. Catalytic hydrogenation was carried out at 4.5 atm of pressure for 6 hours. The solid was
filtered and the filtrate was evaporated to dryness to afford 180 mg of 4d, yield: 95.0%; mp:
158-160 ºC; 1H-NMR δ (ppm) (CDCl3): 2.05 (s, 3H, Ac), 2.07 (s, 3H, Ac), 2.11 (s, 3H, Ac), 2.18 (s,
3H, Ac), 4.01-4.16 (m, 2H, H-5, 6), 4.30 (dd, 1H, J 3.6 Hz, 12.3Hz ), 4.67 (m, 1H, H-5), 5.26-5.42 (m,
13
2H), 6.25 (d, 1H, J 8.7 Hz, H-1), 6.31 (d, 1H, J 3.6 Hz, H-NH), 7.27-8.09 (m, 4H, Ph); C-NMR δ
(ppm) (CDCl3) 20.6 (CH3CO), 20.7 (CH3CO), 20.8 (CH3CO), 20.9 (CH3CO), 51.3 (OCH3), 61.5, 67.4,
69.7, 70.6(C of sugar ring), 90.6 (C-1), 114.3 (Ph), 116.7 (Ph), 117.4 (Ph), 127.0 (Ph), 132.9 (Ph),
149.0 (Ph), 168.7 (C=O), 168.8 (CH3CO), 169.1 (CH3CO), 170.7 (CH3CO), 172.1 (CH3CO); ESI-
TOF-MS: [M+1]+ m/z 467.1; [M+Na]+ m/z 489.1.
3.2.6. Synthesis and Spectral Data of 5a-d
Compounds 4a-d (300 mg) were dissolved in ClCH2CH2Cl (50 Ll), then triphosgene (140 mg,
0.54 mmol) was added. The mixture was refluxed for 6h and cooled to room temperature. CH2Cl2
(50 mL) was added and the organic layer was washed with saturated sodium hydrogen carbonate
solution, saturated brine and water. The organic layer was dried over anhydrous Na2SO4, evaporated
under reduced pressure to dryness, and purified with column chromatography on silica gel to yield
white solids of 5a-d.
Methyl-6-(N3-)quinazolinedionyl-6-deoxy-2,3,4-tri-O-acetyl-α-D-glucopyranoside (5a). Yield: 89.0%;
mp: 118-120 ºC; []D +108o (c 1.01, CHCl3); 1H-NMR δ (ppm) (CDCl3): 2.01 (s, 3H, Ac), 2.05 (s, 3H,
Ac), 2.18 (s, 3H, Ac), 3.20 (s, 3H, OCH3), 4.14 (dd, 1H, J6e, 5 3.9Hz, J6a, 6e 13.5 Hz, H-6e), 4.30 (m, 1H,
H-5), 4.51 (dd, 1H, J6a, 5 8.4 Hz, J6a, 6e 12.9 Hz, H-6a), 4.90 (d, 1H, J1, 2 3.6 Hz, H-1), 4.94 (dd, 1H, J1,2
8.4 Hz, J2,312.9 Hz, H-2),5.09 (t, 1H, J 9.3 Hz, H-4), 5.48 (t, 1H, J 9.3 Hz, H-3), 7.16-8.16 (m, 4H, Ph).
10.2 (s, 1H, H-NH); 13C-NMR δ (ppm) (CDCl3): 20.7 (CH3CO), 39.4 (C-6), 55.0 (OCH3), 67.6 (C-5),
69.2 (C-3), 69.8 (C-2), 70.9 (C-4), 96.8 (C-1), 124.5 (Ph), 129.0 (Ph), 30.5 (Ph), 132.7 (Ph), 133.9
(Ph), 146.2 (Ph), 166.6 (C=O), 169.9 (CH3CO), 170.2 (CH3CO), 170.3 (CH3CO); ESI-TOF-MS:
[M+1]+ m/z 465.0; [M+Na]+ m/z 487.0.
Methyl-6-(N3-)quinazolinedionyl-6-deoxy-2,3,4-tri-O-acetyl-α-D-galactopyranoside
(5b).
Yield:
89.0%, mp: 216-219 ºC; []D +220o (c 1.01, CHCl3); 1H-NMR δ (ppm) (CDCl3): 1.96 (s, 3H, Ac), 2.08
(s, 3H, Ac), 2.26 (s, 3H, Ac), 3.34 (s, 3H, OCH3), 4.29 (m, 2H, H-5,6e), 4.52 (t, 1H, J 6.6 Hz, H-6a),
5.00 (d, 1H, J1, 2 3.3 Hz, H-1), 5.20 (dd, 1H, J1,2 3.3 Hz, J2,3 10.8 Hz, H-2), 5.33 (dd, 1H, J3,4 3.3 Hz, J2,3
13
10.8 Hz, H-3), 5.38 (d, 1H, J 3.0 Hz, H-4), 7.10-8.13 (m, 4H, Ph), 10.1 (s, 1H, H-NH); C-NMR δ
(ppm) (CDCl3): 20.7 (s, 3H, Ac), 20.8 (s, 3H, Ac), 20.9 (CH3CO), 39.8 (C-6), 55.2 (OCH3), 65.2 (C-
5), 67.9 (C-3), 68.1 (C-2), 68.2 (C-4), 97.0 (C-1), 114.2 (Ph), 115.0 (Ph), 123.6 (Ph), 128.5 (Ph), 135.3
(Ph), 138.4 (Ph), 151.6 (C=O), 162.2 (C=O), 170.1 (CH3CO), 170.4 (CH3CO), 170.8 (CH3CO); ESI-
TOF-MS: [M+1]+ m/z 465.1; [M+Na]+ m/z 487.1.

Molecules 2009, 14
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Methyl-6-(N3-)quinazolinedionyl-6-deoxy-2,3,4-tri-O-acetyl-α-D-mannopyranoside
(5c).
Yield:
81.8%; mp: 78-82 ºC; []D +32o (c 1.01, CHCl3); 1H-NMR δ (ppm) (CDCl3): 2.01 (s, 3H, Ac), 2.07, (s,
3H, Ac) 2.16 (s, 3H, Ac), 3.19 (s, 3H, OCH3), 4.14 (dd, 1H, J6e, 5 3.9 Hz, J6a, 6e 13.5 Hz, H-6e), 4.30 (m,
1H, H-5), 4.51 (dd, 1H, J6a, 5 8.4 Hz, J6a, 6e 13.5 Hz, H-6a), 4.60 (dd, 1H, J2,3 2.1 Hz, J1,2 4.8 Hz, H-2),
5.21 (d, 1H, J1, 2 2.1 Hz, H-1), 5.32-8.34 (m, 2H, H-4,3), 7.21-8.16 (m, 4H, Ph). 10.7 (s, 1H, H-NH);
13C-NMR δ (ppm) (CDCl3): 20.6 (CH3CO), 20.7 (CH3CO), 20.9 (CH3CO), 41.9 (C-6), 54.8 (OCH3),
67.3 (C-5), 69.0 (C-3), 69.1 (C-2), 69.5 (C-4), 98.1 (C-1), 114.1 (Ph), 115.2 (Ph), 123.5 (Ph), 128.4
(Ph), 135.2 (Ph), 138.5 (Ph), 152.0 (C=O), 162.2 (C=O), 169.9 (CH3CO), 170.1 (CH3CO), 170.2
(CH3CO); ESI-TOF-MS: [M+1]+ m/z 465.0; [M+Na]+ m/z 487.0.
2-(N3-)quinazolinedionyl-2-deoxy-1,3,4,6-tetra-O-acetyl-β-D-glucopyranoside (5d). Yield: 57.1%; mp:
193-195 ºC; []D +88o (c 1.01, CHCl3); 1H-NMR δ (ppm) (CDCl3): 2.04 (s, 3H, Ac), 2.05 (s, 3H, Ac),
2.11 (s, 3H, Ac), 2.18 (s, 3H, Ac), 4.02-4.32 (m, 4H, H-sugar), 4.67 (m, 1H, H-5), 5.26-5.42 (m, 2H,
H-sugar), 6.33 (d, 1H, J 3.6 Hz, H-sugar), 6.37 (d, 1H, J 8.1 Hz, H-1), 7.01-8.39 (m, 4H, Ph), 10.2 (ds,
1H, H-NH); 13C-NMR δ (ppm) (CDCl3): 20.6 (CH3CO), 20.7 (CH3CO), 20.8 (CH3CO), 20.9
(CH3CO), 51.8 (OCH3), 61.2, 61.5, 67.2, 69.7, 70.6 (C of sugar ring), 90.4 (C-1), 118.3 (Ph), 121.9
(Ph), 126.3 (Ph), 133.3 (Ph), 140.4 (Ph), 153.8 (Ph), 168.6 (C=O), 169.1 (CH3CO), 172.1 (CH3CO),
179.9 (C=O); ESI-TOF-MS: [M+NH4]+ m/z 510.0; [M+Na]+ m/z 515.0; [M+K]+ m/z 530.9.
3.2.7. Synthesis and Spectral Data of 6a-d
The appropriate intermediate 5a-d (130 mg) was dissolved in MeOH (20 mL) and sodium
methoxide (10 mg, 0.18 mmol) was added and the mixture stirred for 30 min. The solution was then
neutralized to pH 6-7 by with resin and filtered. The filtrate was evaporated to dryness to obtain light
yellow solid of 6a-d.
Methyl-6-(N3-)quinazolinedionyl-6-deoxy-α-D-glucopyranoside (6a). Yield: 98%; mp: 137-142 ºC;
[]D +60o (c 1.01, DMSO); 1H-NMR δ (ppm) (DMSO-d6): 2.97 (s, 3H, OCH3), 3.03 (m, 1H), 3.17 (m,
1H), 3.35 (m, 1H), 3.82 (m, 1H), 4.05 (m, 1H), 4.19 (m, 1H), 4.40 (d, 1H, J1, 2 3.0 Hz, H-1); 13C-NMR
δ (ppm) (DMSO-d6): 41.8 (C-6), 53.7 (OCH3), 67.2 (C-5), 71.9 (C-3), 73.2 (C-2), 73.8 (C-4), 99.5 (C-
1), 113.8 (Ph), 115.8 (Ph), 122.0 (Ph), 27.3 (Ph), 134.7 (Ph), 140.7(Ph), 150.9 (C=O), 162.3 (C=O);
ESI-TOF-MS: [M+1]+ m/z 339.0; [M+Na]+ m/z 361.0.
Methyl-6-(N3-)quinazolinedionyl-6-deoxy-α-D-galactopyranoside (6b). Yield: 81.5%; mp: 235-237 ºC;
[]D +220o (c 1.01, MeOH); 1H-NMR δ (ppm) (DMSO-d6): 3.34 (s, 3H, OCH3), 3.49-3.58 (m, 2H),
3.65-3.96 (m, 3H), 4.07 (dd, 1H, 1H, J2,3 3.6 Hz, J3,4 9.3 Hz, H-3), , 4.37 (s, 1H, H-1), 4.42-4.59 (m,
3H); 13C-NMR δ (ppm) (DMSO-d6): 40.9 (C-6), 55.2 (OCH3), 67.1, 68.2, 69.0, 70.2 (C of sugar ring),
99.9 (C-1), 104.2 (C-1), 113.7 (Ph), 115.1 (Ph), 122.4 (Ph), 127.4 (Ph), 135.0 (Ph), 139.4(Ph), 150.4
(C=O), 162.2 (C=O); ESI-TOF-MS: [M+1]+ m/z 339.1; [M+Na]+ m/z 361.0.
Methyl-6-(N3-)quinazolinedionyl-6-deoxy-α-D-mannopyranoside (6c). Yield: 81.0%; mp: 169-172oC;
[]D +60o (c 1.01, DMSO); 1H-NMR δ (ppm) (DMSO-d6): 2.93 (s, 3H, OCH3), 3.39-3.54 (m, 3H, H-5,
6a, 6e), 3.76 (m, 1H), 4.06 (dd, 1H, 1H, J2,3 3.6 Hz, J3,4 9.3 Hz, H-3), 4.27 (dd, 1H, J4,5 9.6 Hz, J3,4 13.2

Molecules 2009, 14
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Hz, H-4), 4.37 (s, 1H, H-1); 13C-NMR δ (ppm) (DMSO-d6): 41.8 (C-6), 53.4 (OCH3), 68.2, 70.1, 70.9
(C of sugar ring), 100.8 (C-1), 113.7 (Ph), 115.1 (Ph), 122.4 (Ph), 127.4 (Ph), 134.9 (Ph), 139.5 (Ph),
150.3 (C=O), 162.1 (C=O); ESI-TOF-MS: [M+1]+ m/z 339.0; [M+Na]+ m/z 361.0.
2-(N3-)quinazolinedionyl-2-deoxy-D-glucopyranoside (6d). Yield: 90.9%; mp:174-179 ºC; []D +20o (c
1.10, DMSO); 1H-NMR δ (ppm) (DMSO-d6): 3.69-3.78 (m, 2H, H-5, H-6), 4.01 (dd, 1H, J6a, 5 3.0 Hz,
J6a, 6e 5.4 Hz, H-6a), 4.60 (t, 1H, J 4.8 Hz), 4.78 (dd, 1H, J2,3 2.4 Hz, J2,1 5.1 Hz, H-2), 5.08 (dd, 1H, J2,3
2.4 Hz, J3,41 5.1 Hz, H-3), 5.54 (d, 1H, J2,1 5.1 Hz, H-1), 6.0 (s, 1H, H-OH), 7.18-7.95 (m, 4H, Ph); 13C-
NMR δ (ppm) (DMSO-d6): 65.9, 69.3, 70.9, 80.6, 84.6 (C-sugar), 100.8 (C-1), 113.7 (Ph), 115.1 (Ph),
122.7 (Ph), 127.5 (Ph), 135.2 (Ph), 139.5 (Ph), 150.0 (C=O), 162.1 (C=O); ESI-TOF-MS: [M+NH4]+
m/z 338.0; [M+Na]+ m/z 347.0.
3.3. Anti-angiogenesic Inhibitory Activity of the Target Compounds
The eggs were cut and chicken embryos were incubated under 37.5 °C for 7 days. When the
CAM‘s diameter had grown to 1-3cm, solutions of the compounds was added to each chicken embryo
with PBS as control. The results were recorded by camera under a dissection microscope [22].
4. Conclusions
In summary, several novel 3-N-sugar-substituted quinazolinediones were synthesized and their anti-
angiogenesis activities were tested. An efficient method, using triphosgene as the carbonylation
condensation reagent, was developed for the synthesis of N-sugar-substituted quinazolinediones. This
method might be useful in the future for the preparation of similar derivatives.
Acknowledgements
This work was supported by the National Science Foundation of China (30672525, 20732001).
References and Notes
1. Fujii, H.; Nakajima, M.; Aoyagi, T. Inhibition of tumor cell invasion and matrix degradation by
aminopeptidase inhibitors. Biol. Pharm. Bull. 1996, 19, 6-10.
2. Siegfried, A.; Janine, T.; Uwe, L. Use of alanyl-aminopeptidase inhibitors and pharmaceutical
compositions containing said inhibitors. WO 2004004750.
3. Renata P.; Erkki K.; Renate K. Aminopeptidase N is a receptor for tumor-homing peptides and a
target for inhibiting angiogenesis. Cancer Res. 2000, 60, 722-727.
4. Ikeda, N.; Nakajima, Y.; Tokuhara, T. Clinical significance of amino peptidase N/CD13
expression in human pancreatic carcinoma. Clin. Cancer Res. 2003, 9, 1503-1508.
5. Hashimoto,Y. Structural development of biological response modifiers based on thalidomide.
Bioorg. Med. Chem. 2002, 10, 461-479.
6. Ma, L.; Rudert, W.A.; Harnaha, J.; Wright, M.; Machen, J. Immunosuppressive effects of
glucosamine. J. Biol. Chem. 2002, 277, 39343-39349.
7. Shaunak, S.; Thomas, S.; Gianasi, E. Polyvalent dendrimer glucosamine conjugates prevent scar
tissue formation. Nat. Biotechnol. 2004, 22, 977-984.

Molecules 2009, 14
2457
8. Michael, J.; Gueguen, G.; Vercauteren, J.; Moreau, S. Triplex stability of oligodeox ynucleotides
containing substituted quinazoline-2,4-(1H, 3H)-dione. Tetrahedron 1997, 53, 8457-8478.
9. Park H.Y.; Choo, M.K; Lee, S.K.; Kim, S.W. Solid-phase combinatorial synthesis and
cytotoxicity of 3-aryl-2, 4-quinazolindiones. Bioorg. Med. Chem. 2002, 10, 517-523.
10. Ryu, C.K.; Shin, K.H.; Seo, J.H.; Kim, H.J. 6-Arylamino-5, 8-quinazolinediones as potent
inhibitors of endothelium–depend ent vasorelaxation. Eur. J. Med. Chem. 2002, 37, 77-82.
11. Kakuta, H.; Koiso, Y.; Takahashi, H.; Nagasawa, K.; Hashimoto,Y. Novel Specific puromycin-
sensitive aminopeptidase inhibitors: 3-(2, 6-Diethylphenyl)-2, 4(1H, 3H) quinazolinedione and N-
(2, 6-Diethylphenyl)-2-amino-4H-3, 1-benzoxazin-4-one. Heterocycles 2001, 55, 1433-1437.
12. Canonne, P.; Akssira, M.; Dahdouh, A.; Kasmi, H.; Boumzebra, M.; Synthesis of chiral 3-
Substituted 2, 4(1H, 3H)-quinazolinediones. Heterocycles 1993, 36, 1305-1314.
13. Aziane, D.; Soukri, M.; Hakmaoui, A.E. A Convenient Synthesis of 5-and 8-Nitroquinazoline-2,
4-dione derivatives. J. Heterocycl. Chem. 2002, 39, 271-276.
14. Larksarp, C.; Alper, H. Palladium-catalyzed cyclocarbonylation of o-iodoanilines with hetero-
cumulenes: regioselective preparation of 4(3H)-quinazolinone derivatives. J. Org. Chem. 2000,
65, 2773-2777.
15. Azizian, J.; Mehrdad, M.; Jadidi, K.; Sarrafi, Y. Rearrangement of 4-imino-(1H, 4H)-3,1-
benzoxazine-2-ones to 2,4-quinazolinediones via an isocyanate carboxamide intermediate.
Tetrahedron Lett. 2000, 41, 5265-5268.
16. Willis, M.C.; Snell, R.H.; Fletcher, A; Woodward, R.L.. Tandem Palladium-Catalyzed Urea
Arylation−Intramolecular Ester Amidation: Regioselective Synthesis of 3-Alkylated 2,4-Quinazo
linediones. Org. Lett. 2006, 8, 5089-5092.
17. Reina, J.J.; Maldonado, O.S.; Tabarani, G.; Fieschi, F.; Rojo, J. Mannose glycoconju gates
functionalized at positions 1 and 6. binding analysis to DC-SIGN using biosensors. Bioconjug.
Chem. 2007, 18, 963-969.
18. Cottaz, S.; Brimacombe, J.S.; Ferguson, M.A.J. An imino-linked carba-disac charide α- -
mannosidase inhibitor. Carbohydr. Res. 1993, 247, 341-345.
19. Shibata, Y.; Kosuge, Y.; Mizukoshi, T.; Ogawa S. Chemical modification of the sugar part of
methyl acarviosin: synthesis and inhibitory activities of nine analogues. Carbohydr. Res. 1992,
228, 377-398.
20. El-Barbary, A.A.; El-Brollosy, N.R.; Pedersen, E.B. Synthesis of 3'-Azido- and 3'-Amino-2', 3'-
dideoxynucleosides from 2, 4-Quinazolinediones. Heterocycles 1994, 38, 2191-2198.
21. Gouilleux, L.; Fehrentz, J.A.; Winternitz, F.; Martinez, J. Solid phase synthesis of chiral 3-
substituted quinazoline-2, 4-diones. Tetrahedron Lett. 1996, 37, 7031-7034.
22. Yang, X.R.; Zhao, B.Z.; Cui, J.R. Anti-angiogenesis of sodium aescinate in vivo. Zhongguo
Xinyao Zazhi 2006, 15, 868-870.
Sample Availability: Samples of the compounds 6a-d are available from the authors.
© 2009 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland.
This article is an open-access article distributed under the terms and conditions of the Creative
Commons Attribution license (http://creativecommons.org/licenses/by/3.0/).