A New Synthetic Route to Avibactam: Lipase Catalytic Resolution and

Dec 7, 2017 - An efficient synthesis of avibactam starting from commercially available ethyl-5-hydroxypicolinate was completed in ten steps and 23.9% ...
3 downloads 121 Views 491KB Size
Subscriber access provided by READING UNIV

Full Paper

A New Synthetic Route to Avibactam: Lipase Catalytic Resolution and the Simultaneous Debenzylation / Sulfation tao wang, Liang-dong Du, Ding-jian Wan, Xiang Li, Xinzhi Chen, and Guofeng Wu Org. Process Res. Dev., Just Accepted Manuscript • DOI: 10.1021/acs.oprd.7b00290 • Publication Date (Web): 07 Dec 2017 Downloaded from http://pubs.acs.org on December 7, 2017

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a free service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are accessible to all readers and citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

Organic Process Research & Development is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 18 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Organic Process Research & Development

A New Synthetic Route to Avibactam: Lipase Catalytic Resolution and the Simultaneous Debenzylation / Sulfation

Tao Wang,a,c Liang-Dong Du,b Ding-jian Wan,bXiang Li,b Xin-Zhi Chen,c* Guo-Feng Wu,a*

a

Research&Development Center, Zhejiang Medicine CO., Ltd, 59 East Huangcheng Road, Xinchang, Zhejiang, 312500, P. R. China

b

Shanghai Laiyi Center for Biopharmaceuticals R&D, 5B, Building 8 200 Niudun Road Pudong District, Shanghai, 201203, P. R. China

c

College of Chemical and Biological Engineering, Zhejiang University, 38 Zhejiang University Road, Xihu District, Hangzhou, 310007, P. R. China

E-mail: [email protected]

1

ACS Paragon Plus Environment

Organic Process Research & Development 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

For Table of Contents Only

2

ACS Paragon Plus Environment

Page 2 of 18

Page 3 of 18 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Organic Process Research & Development

ABSTRACT An efficient synthesis of avibactam starting from commercially available ethyl-5-hydroxypicolinate was completed in ten steps and 23.9% overall yield. The synthesis features a novel lipase-catalyzed resolution, in the preparation of (2S,5S)-5-hydroxypiperidine-2-carboxylate acid, which are valuable precusors of the key intermediate ethyl (2S,5R)- 5-((benzyloxy)amino) piperidine-2-carboxylate. An optimized one-pot debenzylation / sulfation reaction, followed by cation exchange, gave the avibactam sodium salt on a 400.0 gram scale. KEYWORDS Avibactam, Lipase- Catalyzed Resolution, Chiral Isomers , sulfation

3

ACS Paragon Plus Environment

Organic Process Research & Development 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 4 of 18

INTRODUCTION Avibactam (1, Figure 1), sodium (2S,5R)-2-carbamoyl-7-oxo-1,6-diazabicyclo [3.2.1]octan-6-yl

sulfonate,

containing

a

diazabicyclo[3.2.1]octane

(DBO)

heterocyclic core structure, is a novel diazabicyclooctane non-β-lactama β-lactamase inhibitor

1-4

. It has a unique mechanism of inhibition among β-lactamase inhibitors,

which is able to bind reversibly and covalently to β-lactamase

2,5

. As a new drug

featured with bacterial resistance, avibactam has been widely used in clinic and its combination with Ceftazidime (Zavicefta) has recently been approved by EMA and FDA for treatment of complicated intra-abdominal infectious (CIAI), complicated urinary tract infectious (CUTI), hospital acquired pneumonia (HAP) and etc

6,7

.

Moreover, compared with the three known β-lactamase inhibitors named clavulanic acid, sulbactam and tazobactam, the efficiency of avibactam is stronger and its spectrum is also broader: avibactam is active against class A including Class A Klebsiella pneumoniae carbapenemase (KPCs) and ESBLs, class C, and some class D β-lactamases 8,9 .

Figure 1 The Structure of Avibactam Sodium (1)

In the past decades, antibiotics containing highly active β-lactam ring systems, such as Penicillium, Cephalosporins and others, have been widely used to treat bacterial infections in worldwide. Resistance to the β-lactam antibacterials is an increasing serious problem, as is the case for all antibacterials 10,11. Avibactam alone has no useful intrinsic antibacterial activity, but its combination with antibiotics can be used to avoid bacterial resistance and enhance the effect 5, 12, 13. The concept of avibactam has its origins in research from Hoechst Marion 4

ACS Paragon Plus Environment

Page 5 of 18 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Organic Process Research & Development

Roussel, who proposed that DBO might act to acylate nucleophilic enzymes in a manner analogous to β-lactams 14. It has been proved that avibactam has excellent antibacterial activity and plays an irreplaceable role in the treatment of infection with drug-resistant bacteria. Substantial effort has been devoted to the preparation of avibactam 14-26 (Scheme 1). Initially, the Aventis infection division in Romainville (France) disclosed route A for its synthesis in the early stage of drug discovered 17, 19. In this process, double-chiral piperidine derivatives were used as starting material to provide avibactam via inversion

of

configuration,

deprotection,

urea-cyclization,

deprotection

and

sulfonation with about 9.0 % total yields. Miller S·P etal also prepared avibactam based on route A 23. This route suffers from a long synthetic procedure, low yield, and heavy laborious workups. Besides, the raw materials (double-chiral piperidine derivatives) is expensive and a number of environmentally undesirable reagents and solvents are required in this route. The Wockhardt developed route B to obtain avibactam from L-glutamate acid or L-pyroglutamic acid 18. In this route , the skeleton of the target molecular diazabicyclo[3.2.1]octane heterocyclic core structure (DBO) was constructed through the steps of ring-opening, ring-closing, deoxygenization, and then by deprotection, sulfonation and other steps to obtain avibactam with total yield of about 11.0%. This method, producing small scale avibactam in a single batch, has some drawbacks limiting the large-scale synthesis: (a) a long synthetic procedure, (b) complicated purification process , (c) the employment of excessive environmentally unfriendly reagents such as diphosgene. Recently, AstraZeneca and Forest Laboratories

have

optimized

the

process:

from

commercially

available

Boc-benzylglutamate in only 5 isolated steps with an overall yield of 35.0 %( without including the construction of DBO) 26. Another route is based on the olefin metathesis reaction to construct DBO skeleton 24 (Route C). However, the decomposition of olefins generally leads to lower yield, substrate instability, the need for chiral ligand participation , less stereoselectivity and other issues. These methods mentioned above are usually restrictive, and difficult to implement industrial production.

5

ACS Paragon Plus Environment

Organic Process Research & Development 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 6 of 18

Scheme 1. Reported Synthetic Routes to Avibactam

RESULT AND DISCUSSION Based on earlier reports

16-20

, we optimized the process of preparing avibactam

(scheme 2). Three key changes are made: (1) the commercially available and affordable ethyl-5-hydroxypicolinate was used as the starting material, avoiding the ring-opening and carbonized cyclization reaction steps used in previous reported routes;

(2)

a

novel

lipase-catalyzed

resolution

was

used

to

synthesize

(2S,5S)-5-hydroxypiperidine-2-carboxylate acid, which are a valuable precursor of the key intermediate ethyl (2S,5R)-5-((benzyloxy)amino) piperidine-2-carboxylate; (3) an optimized debenzylation-sulfation reaction was developed, and environmental friendly solvents and reagents were used.

6

ACS Paragon Plus Environment

Page 7 of 18 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Organic Process Research & Development

Scheme 2. Our Route to Synthesize Avibactam

New approach to 7 from 2. In our new route (route D), an efficient synthesis of intermediate 7 is crucial to the viability

of

the

project.

Starting

from

commercially

available

ethyl-5-hydroxypicolinate (2) (Scheme 3), compound 3 was obtained with a stereoisomer ratio of 97 : 3 (cis / trans) through the catalytic hydrogenation reaction. Without further purification, the crude 3 underwent the lipase (Lipozyme CALB 21

)-catalyzed resolution to successfully give compound 4 as a single enantiomer with

d.r. ≥ 99 : 1, along with a small amount of the side-product 4' 15b. Subsequently, a mixture of (Boc)2O and TEA was added dropwise to the aqueous solution of 4 and 4’ and the mixture was stirred at room temperature for 18 hours to give (2S,5S)-1-tert-butyl-2-ethyl-5-hydroxy-piperidine-1,2-dicarboxy-late by-product 5'

(5)

and

15b

. Compound5' is water-soluble and was removed by liquid

separation so that pure product 5 was easily obtained. Chemical catalytic methods to prepare 5 directly from compound 3 were also tried, but the stereoselectivity is relatively poor (d.r. ≈ 1 : 1). Overall, compound 5 was obtained using relatively environmental friendly methods and the total yield for the above three steps is up to 42.9%. Next, compound 5 was dissolved in CH3CN and stirred at -30 oC for 30 min. 2,6-Dimethylpyridine and trifluoromethanesulfonic anhydride were successively added to the reaction solution followed by the addition of a solution of NH2OBn in 2,6-dimethylpyridine. The mixture was stirred at room temperature for 12 hours to give compound 6. The key intermediate 7 was afforded by removing the protecting 7

ACS Paragon Plus Environment

Organic Process Research & Development 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 8 of 18

group Boc using TFA. The total yields for the last two step is 75.2%.

Scheme 3. Synthetic Route to the Key Intermediate (7) HO

Rh/C , H2 N

HO

Lipozyme CALB

EtOH

CO2Et

N H

CO2Et Phosphate solution

THF

(S) CO2Et

OBn (R) HN 1) Tf 2O, 2,6-Dimethylpyridine 2)

+

4 (a single enantiomer, dr >99 :1)

HO (S) (S) N CO2Et Boc

HO (R) N H

3 cis/trans = 97 : 3

2

(Boc)2O, TEA

HO (S)

NH2OBn, CH3CN

N Boc

(S) CO2Et

6

5 total yield for the three steps: 42.9% + H (R) HO N (R) N CO2 Boc

TFA

N H 4'

(R) CO2H

OBn(R) HN (S)

DCM

N CO2Et H 7 the yield for the last two steps : 75.2%

5' water soluble

New approach to obtain 10 from 7. An efficient synthesis of pure compound 7 offered new approaches to the synthesis of 10, avoiding the selective hydrolysis of the trans benzyl ester of 8 (Scheme 4). At first, we tried a synthetic route including the urea-unit formation (7 to 8) and the ester to amide conversion (8 to 10). However, the yield was always low for each step. So an alternative strategy was used by reversing the sequence of reaction steps, that is, amide formation first followed by the formation of urea-subunit. Fortunately, when compound 7 was subjected to a solution of NH3 / MeOH/toluene, the amide 9 was obtained with 96.5% yield. Much efforts were devoted to introduce the fragile urea bond in compound 10 (Scheme 4). Initially, we tried the direct urea-unit formation using triphosgene,

but

proved to be unsuccessful. Use of alternative phosgenating agents (such as CDI and various chloroformates) also failed, but these experiments clearly revealed that the two nitrogens in the molecule can be selectivily reacted, which are consistent with report by Matthew Ball et al

26

). Inspired by earlier reports[16,18-20,23,25,26], we

predict that the introduction of Boc or FMOC protecting groups on the nitrogen might 8

ACS Paragon Plus Environment

Page 9 of 18 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Organic Process Research & Development

favor the formation of 10 directly from 9. Due to the much milder deprotection conditions required to remove the FMOC group , the FMOC approach was selected for further studies. Solvent had a significant effect on the outcome of the reaction. Many solvents were screened and chlorobenzene was found to be suitable and facilitate the operable processing. Under the optimized reaction conditions, compound 10 with high quality was successfully prepared with 89% yield. The total yield for the preparation of 10 starting from compound 7 is up to 90%. Scheme 4 Conversion 7 to Urea 10

Synthesis of 13 by one pot Deprotection and Sulfation Significant progress has been made in optimizing the process to synthesize 13 from 10 (scheme 5). Typically, the simultaneous catalytical deprotection of the Bn group with Pd/C as catalyst and sulfation gave the intermediate 12. Without further purification, compound 12 were subjected to a cation exchange reaction to give compound 13. It is worth noting that nucleophilic

enough

to

react

the debenzylative intermediate 11 was

with

the

commercially

available

sulfur

trioxidetrime-thylamine (SO3·NMe3) to form compound 12. Another advantage of the transformation is that a more environmentally friendly water/isopropyl alcohol (1 : 1) system was used to replace other organic solvents. Thus, an efficient synthesis of avibactam was completed in ten steps and 23.9% overall yield.

9

ACS Paragon Plus Environment

Organic Process Research & Development 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Scheme 5 Synthetic Routes to Intermediate 13 and 1

CONCLUSION In summary, we have developed an alternative scalable process for the synthesis of avibactam (1) from commercial available and affordable ethyl 5-hydroxypicolinate(2), validated on a 400.0 g scale. The lipase-catalyzed resolution (Lipozyme CALB) was used to construct the two chiral carbon centers and excellent stereoselectivity was achieved. The efficiency and operability of the formation of the urea-unit of avibactam (1) was greatly improved by introduction of a protecting group strategy. Moreover, the simultaneous debenzylation-sulfation in a one-pot has reduced cost and improved efficiency. Lastly, we chose environmental friendly solvents and reagents, and increased the process efficiency by reducing extractions and easy of purification operation.

EXPERIMENTAL SECTION General. Unless otherwise mentioned, all commercial reagents and solvents were used directly as purchased. Flash chromatography was performed on silica gel with petroleum ether/ethyl acetate or dichloromethane/methanol as the eluent. Melting points were uncorrected. Optical rotations were measured with a sodium lamp. NMR

10

ACS Paragon Plus Environment

Page 10 of 18

Page 11 of 18 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Organic Process Research & Development

spectra were recorded on a spectrometer at 500 MHz (1H NMR), 101 MHz or 126 MHz (13C NMR). The mass data were recorded on a high-resolution mass spectrometer in the ESI mode. Chemical shifts (δ) are reported in parts per million and referenced to the residual solvent peak, and J values are given in hertz (Hz). Preparation of ethyl 5-hydroxypiperidine-2-carboxylate (3) Rh/C (25.0 g, 10%) was added to a mixture of ethyl-5-hydroxypicolinate (2) (250.0 g, 1.496 mol) and ethanol (1500.0 mL) in a vessel. The reaction mixture was stirred under the atmosphere of hydrogen (200.0 psi) at room temperature for 12h until completion of the reaction (by TLC analysis). Then, the mixture was filtered and the solvent was removed under reduced pressure to obtain the crude ethyl 5-hydroxypiperidine-2-carboxylate (3) (253.0 g). The crude 3 was directly used in the next step without further purification. Preparation of ethyl (2S, 5S)-5-hydroxypiperidine-2-carboxylate (4) The crude 3 (253.0 g, 1.460 mol) was dissolved in a potassium phosphate buffer solution (8.53 L, 0.1 M, pH = 8). The pH of the solution was adjusted to 7.5 with dipotassium hydrogen phosphate followed by the addition of Lipozyme CALB (253.0 g, 5000 LU/g ) . The reaction mixture was stirred at room temperature for 12 h until completion of the reaction (by TLC analysis). The aqueous solution of 4 (8.53 L) was obtained by filtration and directly used for the next step. Preparation of (2S, 5S)-1-tert-butyl-2-ethyl-5-hydroxypiperidine-1,2-dicarboxylate (5) Triethylamine (407 mL, 2.92 mol) was added to a mixture of the aqueous solution of 4 (8.53 L)

and THF (8 L) at room temperature. Then (Boc)2O (101.0 g, 1.752 mol)

was added dropwise to the mixture at 0 oC. The reaction mixture was stirred at room temperature for 18 h until completion of the reaction (by TLC analysis). Then, the reaction mixture was extracted three times with ethyl acetate (3 L × 3). The by-product 5' is water-soluble and remained in the aqueous solution. The combined organic layers were dried over anhydrous MgSO4. Evaporation of the solvent under vacuum, followed by flash column chromatography on silica gel (petroleum ether/ethyl acetate = 4/1), gave the corresponding product 5, as a pale yellow liquid 11

ACS Paragon Plus Environment

Organic Process Research & Development 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

1 (175.8 g, the three step total yields : 42.9%), [α]  = −101.59 (c = 0.62, CHCl3); H

NMR (500 MHz, CDCl3) δ 4.73 (d, J = 87.9 Hz, 1H), 4.21 (s, 2H), 4.10 (d, J = 9.0 Hz, 1H), 3.64 (s, 1H), 2.72 (dt, J = 50.3, 11.5 Hz, 1H), 2.29 (s, 1H), 1.98 (d, J = 10.3 Hz, 1H), 1.81 – 1.67 (m, 1H), 1.64 (s, 1H), 1.60 (s, 1H), 1.46 (d, J = 17.5 Hz, 9H), 1.28 (t, J = 6.9 Hz, 3H). 13C NMR (101 MHz, CDCl3) δ 171.47 (s), 155.55 (s), 80.55 (s), 66.57 (d, J = 22.1 Hz), 61.27 (s), 53.35 (d, J = 119.3 Hz), 48.00 (d, J = 84.9 Hz), 30.12 (d, J = 58.6 Hz), 28.29 (s), 24.91 (d, J = 22.5 Hz), 14.22 (s). IR (cm−1): 2979, 1741, 1699, 1403, 1370, 1149, 1073, 1024. MS (ESI) m/z: 296.1 [M+Na]+ Preparation of (2S, 5R)-1-tert-butyl-2-ethyl 5-((benzyloxy) amino) piperidine-1, 2- dicarboxylate (6) 2, 6-dimethylpyridine (95.0 mL, 805.0 mmol) and Tf2O (131 mL, 778 mmol) were added successively, dropwise, to a mixture of 5 (202.0 g, 741.0 mmol) in CH3CN (2000 mL) at -30 oC, and the reaction mixture was stirred at this temperature for 15 min. NH2OBn and 2, 6-dimethylpyridine (95 mL , 805.0 mmol) was slowly added to the reaction solution at -30 oC. Then, the reaction mixture was stirred at 0oC for 30 min and at room temperature for 12 h. The reaction mixture was extracted with ethyl acetate (600 mL × 3), and the combined organic layers were dried over anhydrous MgSO4. Evaporation of the solvent under vacuum gave the corresponding crude product 6 (280.2 g).The crude product 6 was directly used to next step without further purification. The pure product 6 is a white solid, m.p. 122.3−125.2 °C; [α]  = −81.59 (c = 0.63, CHCl3); 1H NMR (500 MHz, CDCl3) δ 7.39 – 7.32 (m, 4H), 7.32 – 7.27 (m, 1H), 5.47 (s, 1H), 4.72 (dd, J = 25.9, 11.5 Hz, 3H), 4.19 (dd, J = 14.0, 7.0 Hz, 3H), 3.14 (t, J = 36.2 Hz, 2H), 1.96 (s, 2H), 1.69 (d, J = 13.9 Hz, 1H), 1.46 (s, 10H), 1.29 – 1.24 (m, 3H). 13C NMR (126 MHz, CDCl3) δ 137.92 (s), 128.53 (s), 128.37 (s), 127.80 (s), 80.19 (s), 76.66 (s), 61.07 (s), 53.68 (s), 53.26 (s), 42.76 (s), 28.37 (s), 22.98 (s), 21.26 (s), 14.28 (s). IR (cm−1): 3242, 2947, 1738, 1674, 1427, 1152, 1195, 1030,701. MS (ESI) m/z: 379.2 [M+H]+ Preperation of ethyl (2S, 5R)-5-((benzyloxy) amino) piperidine-2-carboxylate (7) Trifluoroacetate acid (124.0 mL, 1.665 mol) was added dropwise to the solution of the crude product 6 (280.2 g) in CH2Cl2 (1500 mL) at 0 oC. The mixture was stirred at 12

ACS Paragon Plus Environment

Page 12 of 18

Page 13 of 18 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Organic Process Research & Development

r.t. for 15h. The pH of reaction solution was adjusted to 10 with saturated sodium bicarbonate solution. Then, the reaction mixture was extracted with DCM (600 mL × 3), and the combined organic layers were dried over anhydrous MgSO4. Evaporation of the solvent under vacuum, followed by flash column chromatography on silica gel (DCM/MeOH = 20/1)), gave the corresponding crude product 7, as a pale yellow liquid (155.4g, the two step total yields : 75.2% ), [α]  = -10.40 (c = 0.92, CHCl3); 1

H NMR (500 MHz, CDCl3) δ 7.41 – 7.32 (m, 4H), 7.33 – 7.21 (m, 1H), 4.89 – 4.42

(m, 2H), 4.18 (q, J = 7.1 Hz, 2H), 3.38 (ddd, J = 11.9, 4.0, 1.8 Hz, 1H), 3.27 (dd, J = 11.0, 3.1 Hz, 1H), 2.99 (tt, J = 10.5, 4.0 Hz, 1H), 2.44 (dd, J = 11.9, 9.8 Hz, 1H), 2.07 (ddd, J = 17.0, 8.5, 4.6 Hz, 1H), 2.01 – 1.89 (m, 1H), 1.53 (tdd, J = 13.0, 11.1, 3.8 Hz, 1H), 1.27 (t, J = 7.1 Hz, 3H). 13C NMR (101 MHz, CDCl3) δ 173.07 (s), 137.78 (s), 128.37 (s), 127.84 (s), 76.78 (s), 60.84 (s), 58.41 (s), 57.10 (s), 49.44 (s), 28.10 (s), 28.01 (s), 14.20 (s). IR (cm−1): 3270, 2930, 1736, 1453, 1191, 1033, 746, 695. MS (ESI) m/z: 279.0 [M + H]+. Preperation of (2S,5R)-5-((benzyloxy)amino)piperidine-2-carboxamide (9) Ethyl (2S, 5R)-5-((benzyloxy) amino) piperidine-2-carboxylate 7 (593.0g, 2.130 mol) was mixed with a solution of 7M ammonia in methanol (2 L). The reaction mixture was stirred at r.t for 8 h until completion of the reaction (by TLC analysis). The solid was removed by filtration and the obtained cake was washed with methanol (2 x 0.5 L). The filtrates were combined and concentrated under vacuum to 1.50 L (Cautiouly, warming from 0oC) followed by the addition of toluene (3 L). This operation is repeated twice in succession. The obtained solution was stirred at 80 oC for 0.5 h.Then it was cooled to 0 oC. The crude product 9 precipitated and was obtained by filtration and washed with methyl tert-butyl ether (1000 mL × 3) and dried in vacuum to give the pure 9 as a white solid (510.1 g, 96.5%), m.p. 148.2−150.9 °C; [α]  = −19.20. (c = 0.36, CHCl3); 1H NMR (400 MHz, DMSO) δ 7.58 – 7.17 (m, 5H), 7.10 (s, 1H), 6.92 (s, 1H), 6.48 (d, J = 6.0 Hz, 1H), 4.57 (s, 2H), 3.13 (dd, J = 11.9, 2.4 Hz, 1H), 2.87 (dd, J = 11.0, 2.7 Hz, 1H), 2.81 – 2.68 (m, 1H), 2.21 (dd, J = 11.8, 10.2 Hz, 1H), 1.88 – 1.76 (m, 2H), 1.34 – 1.20 (m, 1H), 1.11 (ddd, J = 17.5, 12.9, 4.0 Hz, 1H). 13

C NMR (101 MHz, CDCl3) δ 176.31 (s), 137.69 (s), 128.45 (s), 128.43 (s), 127.94 13

ACS Paragon Plus Environment

Organic Process Research & Development 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 14 of 18

(s), 76.90 (s), 59.74 (s), 57.01 (s), 49.25 (s), 28.17 (s), 27.76 (s). IR (cm−1): 3378, 2946, 1624, 1438, 1323, 1122, 824, 698. MS (ESI) m/z: 250.2 [M + H]+. Preperation

of

(2S,5R)-6-(benzyloxy)-7-oxo-1,6-diazabicyclo[3.2.1]octane-2-

carboxamide (10) (2S,5R)-5-[(benzyloxy)amino]piperidine-2-carboxamide 9 (510.1 g, 2.045 mol) was mixed with di-isopropylethylamine (381 mL, 2.188 mol) and chlorobenzene (3.0 L) at 20 °C. The solution of 9-Fluorenylmethyl chloroformate (540.2 g, 2.086 mol) in chlorobenzene (3.1 L) was added to the reaction mixture.The mixture was stirred at 30 °C until completion of the reaction. Then carbonyl diimidazole (331.3 g, 2.658 mol,dropwisely) was added and agitation was continued at 15 °C for 11 h until completion of the reation. Diethylamine (529 mL , 5.112 mol) was added and agitation was continued at r.t. for 2 h Aqueous 3 M hydrochloric acid (3.2 L, 9.600 mol) was added (to achieve a pH of 2 to 6) and the mixture was cooled to 0 °C. The solid was isolated by filtration, washed with water (1.50 L × 2.0) and 1-chlorobutane (1.50 L × 2.0), and dried to give the title compound as a white crystalline solid (495.0 1 g, 89%), m.p. 154.2−156.1 °C; [α]  = −23.57 (c = 0.65, CHCl3); H NMR (400

MHz, DMSO) δ 7.45 (dd, J = 7.8, 1.6 Hz, 2H), 7.43 – 7.33 (m, 4H), 7.30 (s, 1H), 4.93 (q, J = 11.3 Hz, 2H), 3.69 (d, J = 6.9 Hz, 1H), 3.62 (s, 1H), 2.90 (s, 2H), 2.22 – 1.94 (m, 1H), 1.93 – 1.76 (m, 1H), 1.75 – 1.50 (m, 2H). 13C NMR (101 MHz, CDCl3) δ 172.27 (s), 167.70 (s), 135.60 (s), 129.24 (s), 128.84 (s), 128.59 (s), 78.30 (s), 59.18 (d, J = 253.0 Hz), 57.92 (s), 47.80 (s), 20.86 (s), 17.31 (s). IR (cm−1): 3406, 2991, 1761, 1663, 1455, 1386, 1022, 755. MS (ESI) m/z: 298.1[M + Na]+. Preparation of Tetrabutylammonium [(2S, 5R)-2-Carbamoyl-7-oxo-1, 6-diazabicyclo[3.2.1]octan-6-yl] Sulfate (13) (2S,5R)-6-(Benzyloxy)-7-oxo-1,6-diazabicyclo[3.2.1]octane-2-carboxamide

10

(495.0 g, 1.792 mol) was mixed with sulfur trioxide trimethylamine complex (301.0 g, 2.150 mol), triethylamine (65 mL, 890 mmol), 10% w/w Pd/C (40 g, 0.025 wt), isopropanol (2.50 L), and water (2.50 L). This mixture was then held in a hydrogenation vessel and flushed with nitrogen at ambient pressure. Hydrogen was then fed into the vessel at 0.4 mol equiv per hour until the debenzylation reaction was 14

ACS Paragon Plus Environment

Page 15 of 18 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Organic Process Research & Development

completed. The catalyst was removed by filtration and washed with water. The combined filtrates were washed with n-butyl acetate (2.0 L). A solution of tetrabutylammonium acetate (812.0 g, 2.698 mol), acetic acid (11 g, 180 mmol) in water (1.00 L) was prepared. 72% of the tetrabutylammonium acetate solution was added to the reaction mixture, which was then extracted with DCM (2.00 L). The remaining 28% of the tetrabutylammonium acetate solution was added to the reaction mixture which was then extracted with DCM (1.50 L). The organic extracts were combined

and

concentrated

to

1.50

L

followed

by

the

addition

of

4-methyl-2-pentanone (1.25 L). The reaction mixture was cooled to 0 °C to precipitate the desired product 13. Compound 13 was collected by filtration and washed with 4-methyl-2-pentanone (1.00 L), and was dried to yield a white crystalline solid 13 (814.0 g, 89.6%), m.p. 180.3−182.4 °C (decomposition); [α]  = −23.20 (c = 0.57, CHCl3); 1H NMR (500 MHz, DMSO) δ 7.36 (d, J = 78.9 Hz, 1H), 3.98 (s, 1H), 3.68 (d, J = 6.6 Hz, 1H), 3.33 (s, 1H), 3.27 – 3.12 (m, 4H), 3.01 (d, J = 11.6 Hz, 1H), 2.92 (d, J = 11.7 Hz, 1H), 2.14 – 1.97 (m, 1H), 1.84 (d, J = 6.0 Hz, 1H), 1.66 – 1.47 (m, 5H), 1.44 – 1.18 (m, 4H), 0.94 (t, J = 7.3 Hz, 6H). 13C NMR (101 MHz, CDCl3) δ 172.29 (s), 166.04 (s), 60.52 (s), 58.69 (s), 57.86 (s), 48.13 (s), 23.95 (s), 20.78 (s), 19.71 (s), 17.24 (s), 13.68 (s). IR (cm−1): 3474, 2964, 1761, 1694, 1488, 1272, 1007, 612. MS (ESI) m/z: 288.0[M + Na]+. Preparation of Avibactam Sodium Salt (1) A solution of sodium 2-ethyl hexanoate (475.0 g, 2.850 mol) in ethanol (2.00 L) was added to a solution of tetrabutylammonium [(2S,5R)-2-carbamoyl-7-oxo-1,6diazabicyclo-[3.2.1]octan-6-yl] sulfate 13 (723.0 g) in ethanol (2.50 l) and water (50 mL ) over approximately 1 h and the temperature was maintained at r.t. The reaction mixture was held for 2 h. The product was filtered, washed with ethanol (2 × 2.0 L), and dried to yield a white crystalline solid 1 (395.0 g, 96.2%), m.p. 259.1−262.4 °C(decomposition); [α]  = −46.40 (c = 0.79, MeOH/H2O = 1/1); 1H NMR (500 MHz, D2O) δ 4.15 (dd, J = 5.8, 2.8 Hz, 1H), 4.01 (d, J = 7.5 Hz, 1H), 3.28 (d, J = 12.2 Hz, 1H), 3.06 (d, J = 12.2 Hz, 1H), 2.23 – 2.09 (m, 1H), 2.06 – 1.96 (m, 1H), 1.94 – 1.82 (m, 1H), 1.81 – 1.69 (m, 1H). 13C NMR (126 MHz, D2O) δ 174.72 15

ACS Paragon Plus Environment

Organic Process Research & Development 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

(s), 169.53 (s), 60.43 (s), 59.93 (s), 47.33 (s), 20.03 (s), 18.31 (s). IR (cm−1): 3459, 1749, 1675, 1361, 1270, 1013, 857, 768. MS (ESI) m/z: 279.0 [M + H]+.

AUTHOR INFORMATION corresponding Athour *Guo-feng Wu

E-mail:[email protected]

*Xin-zhi Chen

E-mail:[email protected]

ACKNOWLEDGMENT The authors would like to thank the Research&Development Center, Zhejiang Medicine CO. and Zhejiang University. The research was supported in part by Zhejiang Province Human Resources and Social Security Department. Supporting Information Available. The Supporting Information is available free of charge on the ACS Publications website. Chiral Hplc Report of Compound 5 (PDF) Copies of 1H and 13C NMR spectra of compounds (PDF)

REFERENCES 1) Bonnefoy, A.; Dupuis-Hamelin, C.; Steier, V.; Delachaume, C.; Seys, C.; Stachyra, T.; Fairley, M.; Guitton, M.; Lampilas, M. Journal of Antimicrobial Chemistry 2004, 54 (2), 410−417. 2) Aszodi, J.; Fromentin, C.; Lampilas, M.; Rowland, D. WO20033063864, 2003. 3) Ehmann, D. E.; Jahić, H.; Ross, P. L.; Gu, R. F.; Hu, J.; Kern, G.; & Fisher, S. L. Proc Natl Acad Sci , 2012, 109(29): 11663-11668. 4) Zhanel, G. G.; Lawson, C. D.; Adam, H.; Schweizer, F.; Zelenitsky, S.; Lagacé-Wiens, P. R.; Denisuik ,A; Rubinstein, E; Gin, A. S; Hoban, D. J; Lynch, J. P. Drugs, 2013, 73(2): 159-177. 5) Coleman, K. Curr Opin Microbiol, 2011, 14(5): 550-555. 6) Stachyra T; Péchereau M C; Bruneau J M; Claudon, M., Frère, J. M., Miossec, C.; Coleman . K; Black, M. T. Antimicrob Agents Chemoth, 2010, 54(12): 16

ACS Paragon Plus Environment

Page 16 of 18

Page 17 of 18 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Organic Process Research & Development

5132-5138. 7) NXL104

Inhibition

of

beta-lactamases[C].CHI-San

Diego

Challenge

of

Antibacterial Drug Development ,2007. 8) Lahiri, S . D; Mangani, . S; Durand-Reville, Benvenuti, M.; De Luca, F.; Sanyal, G., & Docquier, J. D. Antimicrob Agents Chemoth, 2013, 57(6): 2496-2505. 9) (a) Bonnefoy A, Dupuis-Hamelin C, Steier V, Delachaume, C., Seys, C., Stachyra, T. & Lampilas, M. J Antimicrob Chemoth, 2004, 54(2): 410-417. (b) US FDA. FDA approves new antibacterial drug Avycaz [ EB / OL ] . [ 2014-02-25 ] 10) MacVane S H, Crandon J L, Nichols W W, & Nicolau, D. P. Antimicrob Agents Chemoth, 2014, 58(11): 6913-6919. 11) Ehmann D E, Jahić H, Ross P L, Gu, R. F., Hu, J., Durand-Réville, T. F., Palmer,. J Biol Chem, 2013, 288(39): 27960-27971. 12) (a). Aszodi J, Rowlands D A, Mauvais P, Collette, P., Bonnefoy, A., & Lampilas, M. Bioorg Med Chem Lett, 2004, 14(10): 2489-2492. (b) Versporten A, Bolokhovets G, Ghazaryan L, Abilova, V., Pyshnik, G., Spasojevic, T., Carp. Lancet Infect Dis, 2014, 14(5): 381-387. 13) Chahine E B, Sourial M, Ortiz R. Consult Pharm®, 2015, 30(12): 695-705. 14) Dubreuil L J, Mahieux S, Neut C, Miossec, C., Pace, J. Int J Antimicrob Ag, 2012, 39(6): 500-504. 15) (a)Mangion IK, Ruck RT, Rivera N, Huffman MA, Shevlin M. Org.Lett. 13(20), 5480–5483 (2011). (b) Krishnamurthy, S., Venkataprasad, J., Vagvala, T. C., Moriguchi, T., Tsuge, A. RSC Advances, 5(64), 52154-52160. 16) (a) Aventis Pharma SA: WO2002010172, 2002. (b) AstraZeneca: WO2012172368, 2012. (c) Merck: WO2009091856, 2009. (d) Merck: WO2012086241, 2012. 17) (a) Aszodi, J., Lampilas, M., Fromentin, C., & Rowlands, D. A. (2003). Aventis Pharma SA, FR, 2835186. (c) Novexel: WO2008142285, 2008. 18) (a) Patil V J, Tadiparthi R, Birajdar S, Bhagwat, S. P, US8969334, 2015. (b) Hecker E A, Baldwin A. B-lactamase inhibitor picoline salt: P, US9120796, 2015. (c) Aszodi J, Fromentin C, Lampilas M, Rowlands, D. A. P, US7612087, 2009. (d) Gu Y G, He Y, Yin N, Alexander, Dylan. P, WO2013149136, 2013. (e) Hwang Y S, 17

ACS Paragon Plus Environment

Organic Process Research & Development 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Gu J Q, Jain A, Garad S, Jacob P.S. P, US20140275001, 2014 (f) Hecker E A, Baldwin A. P, US20159120796, 2015. 19) Baldwin J E, Adlington R M, Godfrey, C. R., Gollins, D. W., Smith, M. L., & Russel, A. T. Synlett, 1993, 1993(01): 51-53. 20) Abe T, Okue M, Sakamaki Y. P , U.S.8,772,490, 2014-7-8. 21) (a)Pietruszka J, Simon R C, Kruska F, Braun, M. Eur J Org Chem, 2009, 2009(35): 6217-6224. (b) Benjamin A. Anderson, Marvin M. Hansen, Allen R. Harkness, Cynthia L. Henry, Jeffrey T. Vicenzi, Milton J. Zmijewski. J. Am. Chem. Soc, 1995, 117(49): 12358-12359. c) Yoshihiko Hirose, Kinya Kariya, Ikuharu Sasaki, Yoshiaki Kurono, Hirosato Ebiikea, Kazuo Achiwaa. Tetrahedron Lett, 1992, 33(47): 7157-7160 22) (a)Mangion, I. K, Ruck R T, Rivera N, Huffman, M. A., & Shevlin, M. Org Lett, 2011, 13(20): 5480-5483. (b) Chavan, V. P, Wankhede K S, Deshmukh V V, Bhavsar, S., Patil, K. R., Yeole, R. D., Patel, M. V. U.S. Patent Application 15125,554, 2015-3-12. 23) Miller, S. P, Zhong Y L, Liu Z, Simeone, M., Yasuda, N., Limanto, J., Chen, Z.,Lynch, J., Capodanno, V. Org Lett, 2013, 16(1): 174-177. 24) Xiong, H., Chen, B., Durand-Réville, T. F., Joubran, C., Alelyunas, Y. W., Wu, D., Huynh, H. ACS Med Chem Lett, 2014, 5(10): 1143-1147. (b) Launay, O., Joly-Guillou, M. L., Decre, D., & Cremieux, A. C. 1997, 26(10), 485-492. 25) Priour, A.; Bonnet, A.; Oddon, G.; Mazurie, A. WO2009090320, 2009. (b) Lampilas, M.; Aszodi, J.; Rowlands, D. A.; Fromentin, C. WO2002010172, 2002. (c) Dedhiya, M. G., Bhattacharya, S., Ducandas, V., Giuliani, A., Ravaux, V., Bonnet, A .; Priour, A.; Spargo, P. U.S. 8471025, 2013. 26) Ball, M., Boyd, A., Ensor, G. J., Evans, M., Golden, M., Linke, S. R., Milne, D., Murphy, R., Telford, A., Kalyan, Y., Lawton, G. R., Racha, s., Zhou, S. H. Org Process Res Dev, 2016, 20(10): 1799-1805.

18

ACS Paragon Plus Environment

Page 18 of 18