KR960007603B1

KR960007603B1 - PREPARATION PROCESS OF ASPARTAME HYDROCHLORIDE FROM N-FORMYL-Ñß, ÑÔ-L-ASPARTAME

Info

Publication number: KR960007603B1
Application number: KR1019920009807A
Authority: KR
Inventors: 최경석; 한민수; 황이남; 최홍규
Original assignee: 주식회사 미원; 유영학
Priority date: 1992-06-05
Filing date: 1992-06-05
Publication date: 1996-06-07
Also published as: KR940000423A

Abstract

The salt is prepared by (a)removing formyl group by reacting N-formyl- M, Ù-L-astartyl-L-phenyl alanine methylester with acetic acid in hydrochloric acid soln. at 30-90deg.C; (b)adding methanol to the reaction soln. obtd. by (a), and agitating at 30-45deg.C for 0.5-2hrs; (c)adjusting the temp. of soln. to 0-10deg.C while agitating for 12-148hrs. to extract the crystal of M-L-aspartyl-L-phenyl alanine methylester hydrochloric acid salt.

Description

A method for preparing aspartame hydrochloride from N-formyl-α, β-L-aspartame.

본 발명은 인공감미료인 α-L-아스파틸-L-페닐알라닌 메틸에스테르(이하 α-APM, 또는 α-아스파탐이라 칭함)을 제조하는데 있어서, 그 중간체인 N-포밀-α,β-L-아스파닐-L-페닐알라닌 메틸에스테르로부터 보호기인 포밀기를 제거하고, α-L-아스파틸-L-페닐알라닌 메틸에스테르 염산염을 제조하는 방법에 관한 것이다.The present invention is to prepare an artificial sweetener α-L-aspartyl-L-phenylalanine methyl ester (hereinafter referred to as α-APM, or α-aspartame), the intermediate N-formyl-α, β-L-aspa It is related with the method of removing the formyl group which is a protecting group from the nil-L-phenylalanine methyl ester, and manufacturing (alpha) -L-aspartyl-L-phenylalanine methyl ester hydrochloride.

펩타이드 아미노기의 보호기인 포밀기를 제거하는 방법은 각종 문헌「J. C Sheehan and D.D.H.Yang, J.Am, Chem. Soc., 80, 1154(1958) ; G.Losse and D. Nadolski, J. Prakt. Chem., 24,118(1964)]에 일찍부터 보고되어 있으며, 미국특허 USP 4,684,745와 USP 4,071,511 등에도 보고되어 있다.Methods for removing the formyl group, which is a protecting group of the peptide amino group, are described in various J. C Sheehan and D. D. H. Yang, J. Am, Chem. Soc., 80, 1154 (1958); G. Losse and D. Nadolski, J. Prakt. Chem., 24,118 (1964), and is also reported in US Pat. Nos. 4,684,745 and USP 4,071,511.

이중 USP 4,684,745에 의하면 아미노 보호기인 포밀기를 제거하는데 있어서 메틸알콜(이하 MeOH라 함) 수용액에 염산을 첨가하여 포밀기를 제거함으로써 아스파탐 염산염을 제조하는 방법이 기재되어 있으며, US 4,071,511에는 이소프로파놀(iso-propanol), s-부탄놀(sec-butandol), t-부타놀(tert-butanol), 아세톤(Acetone), 아세토니트릴 메틸에틸케톤(Acetonitrile methylethyl ketone) 등을 염산 또는 황산과 혼합하여 보호기를 제거하는 방법이 기재되어 있다.US Pat. No. 4,684,745 describes a method for preparing aspartame hydrochloride by removing hydroformin by adding hydrochloric acid to an aqueous solution of methyl alcohol (hereinafter referred to as MeOH) to remove the formyl group, an amino protecting group, and isopropanol in US Pat. No. 4,071,511. (iso-propanol), s-butandol, t-butanol, tert-butanol, acetone, acetonitrile methylethyl ketone, and the like A method for removing is described.

그러나 USP 4,684,745에 의한 방법은 탈보호시 α,β-L-아스파틸-L-페닐알라닌 디메틸에스테르(이하, α,β-MAPM이라 칭함)가 생성되는 단점이 있고, 동시에 염산에 의하여 α,β-L-아스파틸-L-페닐알라닌(이하 α,β-AP라 칭함)이 생성되는 단점이 있다. 한편 USP 4,071,511에 기재된 방법은 보호기를 제거할때 생성된 α,-AP를 α,β-APM·HCl로 전환시키지 못하는 단점이 있다.However, the method according to USP 4,684,745 has a disadvantage in that α, β-L-aspartyl-L-phenylalanine dimethyl ester (hereinafter referred to as α, β-MAPM) is produced upon deprotection, and at the same time, α, β- There is a disadvantage in that L-aspartyl-L-phenylalanine (hereinafter referred to as α, β-AP) is produced. On the other hand, the method described in US Pat. No. 4,071,511 has a disadvantage in that it does not convert α, -AP generated when the protecting group is removed to α, β-APM.HCl.

또, USP 4,684,745에 기재된 방법처럼 MeOH와 염산수용액을 사용하면 5∼20% 정도의 α,β-APM이 α,β-MAPM으로 전환될 수가 있다. 이는 결국 α-APM 염산염 결정 수율을 감소시키는 원인이 되며, USP 4,071,511의 방법은 염산 수용액에서 MeOH이 아닌 다른 유기용매를 혼합하여 보호기를 제거하기 때문에 α,β-APM이 α,β-AP로 전환되어 모액중으로 폐기되는 것에 의해 수율이 낮아지게 되고 β-APM·HCl를 α-APM·HCl로 이성화 시킬 수 없는 단점을 포함하고 있다.In addition, using MeOH and an aqueous hydrochloric acid solution as described in US Pat. No. 4,684,745, 5 to 20% of α, β-APM can be converted to α, β-MAPM. This in turn causes a decrease in α-APM hydrochloride crystal yield, and the method of USP 4,071,511 converts α, β-APM to α, β-AP because hydrochloric acid solution is mixed with an organic solvent other than MeOH to remove the protecting group. This results in a low yield due to waste disposal in the mother liquor and includes the disadvantage of incapable of isomerizing β-APM HCl with α-APM HCl.

따라서 본 발명의 목적은 α,β-MAPM의 생성 미 β-APM이 α-APM으로 전환되는 이성화(Isomerization)가 불가능한점 등의 단점을 지닌 종래 기술의 단점을 보완하여, α-AP·HCl은 α-APM·HCl로 전환시키고 동시에 β-AP·HCl은 β-APM·HCl로 전환시킨 뒤, α-APM·HCl로 이성화시킴으로써 종래의 방법보다 높은 수율로 α-APM 염산염을 얻을 수 있는 방법을 제공하는 것이다.Accordingly, an object of the present invention is to compensate for the disadvantages of the prior art with the disadvantage that the production of α, β-MAPM and β-APM is not converted to α-APM. By converting to α-APM-HCl and simultaneously converting β-APM-HCl to β-APM-HCl and isomerizing to α-APM-HCl, α-APM hydrochloride can be obtained in a higher yield than the conventional method. To provide.

상기한 본 발명의 목적은 N-포밀-α,β-L-아스파틸-L-페닐알라닌 메틸 에스테르로부터 α-L-아스파틸-L-페닐알라닌 메틸에스테르 염산염을 제조하는 방법에 있어서, 하기 (a)-(c)의 단계 : (a) N-포밀-α,β-L-아스파틸-L-페닐알라닌 메틸에스테르를 염산 수용액중에서 30∼90℃의 온도에서 빙초산과 반응시켜 상기 화합물로부터 포밀기를 제거하는 단계 ; (b) 상기 (a)단계에서 얻은 반응액에 메탄올을 첨가하고 3-45℃의 온도범위에서 0.5-2시간동안 교반하는 단계 ; 및 (c) 반응액을 12-148시간동안 교반하면서 반응액의 온도를 0-10℃의 범위로 조절하여 α-L-아스파닐-L-페닐알라틸 메틸에스테르 염산염의 결정을 석출하는 단계를 포함함을 특징으로 하는 α-L-아스파닐-L-페닐알라틸 메틸에스테르 염산염을 제조방법에 의해 달성된다.The above object of the present invention is a method for preparing α-L-aspartyl-L-phenylalanine methyl ester hydrochloride from N-formyl-α, β-L-aspartyl-L-phenylalanine methyl ester, the method comprising the following (a) Step of (c): (a) N-formyl-α, β-L-aspartyl-L-phenylalanine methylester is reacted with glacial acetic acid in an aqueous hydrochloric acid at a temperature of 30-90 ° C. to remove the formyl group from the compound. Doing; (b) adding methanol to the reaction solution obtained in step (a) and stirring for 0.5-2 hours at a temperature in the range of 3-45 ° C; And (c) adjusting the temperature of the reaction solution to a range of 0-10 ° C. while stirring the reaction solution for 12-148 hours to precipitate crystals of α-L-aspanyl-L-phenylalyl methyl ester hydrochloride. Α-L-aspanyl-L-phenylalyl methyl ester hydrochloride, characterized in that it is achieved by a process for the preparation.

이하 본 발명을 보다 상세히 설명한다.Hereinafter, the present invention will be described in more detail.

본 발명의 방법은 아미노 보호기인 포밀기 제거시 염산 수용액에 빙초산을첨가함으로써 MAPM의 생성을 방지하고, 동시에 초산에 의하여 β-APM이 α-APM으로 이성화 되게 함으로써 α-APM의 수율을 향상시키는 것을 특징으로 한다.The method of the present invention prevents the production of MAPM by adding glacial acetic acid to aqueous hydrochloric acid upon removal of the formyl group, an amino protecting group, and at the same time improving the yield of α-APM by allowing β-APM to isomerize to α-APM by acetic acid. It features.

α,β-FAPM으로부터 보호기인 포밀기를 제거하는 것에 의해 성성된 α-APM과 β-APM중 β-APM이 α-APM으로 이성화되는 과정은 다음 반응식 1과 같다.The process of isomerizing β-APM in α-APM and β-APM formed by removing the formyl group as a protecting group from α, β-FAPM is shown in Scheme 1 below.

위 반응식 1은 포밀-α,β-APM(F-a,β-APM)으로부터 보호기인 포밀기를 제거하는 과정에서 생성된 β-APM 염산염이 일정량의 빙초산(glacial Acetic Acid : 이하 gla-AcOH라 칭함)이 첨가된 염산 수용액 중에서 α-APM으로 이성화되는 기작(isomerization mechanism)을 보여주고 있다. 보호기제거시 빙초산의 존재하에서 이성화 과정이 가능한 이유는 β-APM염산염은 수용액에서의 용해도가 α-APM 염산염에 비해 매우 높고(약 100배), 따라서, 염산빙초산 수용액 중에서 포밀-β-APM으로부터 생선된 β-APM 염산염, α-APM 염산염으로 이성화(Isomerization)되어 α-APM 염산염의 결정으로 석출되기 때문이다.In Scheme 1, β-APM hydrochloride produced in the process of removing formyl group as a protecting group from formyl-α, β-APM (Fa, β-APM) has a certain amount of glacial acetic acid (hereinafter referred to as gla-AcOH). This isomerization mechanism is shown in the added hydrochloric acid aqueous solution. The reason for the isomerization process in the presence of glacial acetic acid when removing the protecting group is that β-APM hydrochloride has a very high solubility in aqueous solution compared to α-APM hydrochloride (about 100 times), and therefore, fish from formyl-β-APM in aqueous glacial acetic acid solution. This is because isomerization with β-APM hydrochloride and α-APM hydrochloride resulted in precipitation of crystals of α-APM hydrochloride.

포밀기 제거단계에서 사용되는 농염산(35%)의 양은 출발물질인 N-포밀-α,β-L-아스파틸-L-페닐알라닌 메틸에스테르 1몰(322g)에 대하여 약 30-100%(v/w)의 범위내에 있고, 물의 양은 역시 N-포밀-α,β-L-아스파틸-L-페닐알라닌 메틸에스테르 1몰(322g)에 대하여 약 30-200%(v/w)의 범위내에 있다. 출발물질에 첨가되는 농염산은 포밀 제거 단계시에 한꺼번에 모두 첨가되거나(실시예 1) 또는 포밀 제거단계와 메탄올 첨가단계에서 나누어 분할 첨가할 수도 있다(실시예 2). 염산 수용액에 첨가되는 빙초산 또는 초산의 양은 N-포밀-α,β-L-아스파틸-L-페닐알라닌 메틸에스테르 1몰(322g)에 대하여 순수 초산으로 환산하여 약 5-100%(v/w)의 범위내에 있다.The amount of concentrated hydrochloric acid (35%) used in the formyl removal step is about 30-100% (v) relative to 1 mole (322 g) of N-formyl-α, β-L-aspartyl-L-phenylalanine methyl ester as a starting material. / w) and the amount of water is also in the range of about 30-200% (v / w) for 1 mole (322 g) of N-formyl-α, β-L-aspartyl-L-phenylalanine methylester. . The concentrated hydrochloric acid added to the starting material may be added all at once during the formyl removal step (Example 1), or may be added separately in the form of the formyl removal step and the methanol addition step (Example 2). The amount of glacial acetic acid or acetic acid added to the aqueous hydrochloric acid solution is about 5-100% (v / w) in terms of 1 mole (322 g) of N-formyl-α, β-L-aspartyl-L-phenylalanine methyl ester in terms of pure acetic acid. Is in the range of.

한편, 염산 수용액중에 MeOH를 사용하지 않고 gla-AcOH 또는 초산을 사용하여 아미노 보호기인 포밀기를 제거하는 것에 의해 F-α,β-APM으로부터 소량 생성되는 α,β-AP는 α-APM 염산염 결정화시에 MeOH를 일정량 첨가하는 것에 의해 α-APM 염산염으로 전환된다. 즉, 포밀기를 제거한 후, 반응액에 메탄올을 N-포밀-α,β-L-아스파틸-L-페닐알라닌 메틸에스테르 1몰(322g)에 대하여 약 10-100%(v/w)의 양으로 첨가하고, 30∼45℃ 정도로 0.5∼2시간 유지시킨 다음 서서히 냉각, 결정화하는 동안 α-AP는 에스테르화되어 α-APM 염산염의 형태로 결정으로서 석출되고, β-AP는 β-APM 염산염으로 전환되고 다시 초산에 의하여 α-APM 염산염으로 이성화가 가능하게 된다. 이때, MeOH에 의한 α,β-AP의 에스테르화와 초산에 의한 β-APM의 이성화 과정을 충분하게 하기 위하여 온도를 서서히 내려 10℃∼0℃에서 12∼148시간 까지 교반함으로써 종래의 방법보다 대단히 높은 수율로 α-APM 염산염을 제조할 수 있게 된다.On the other hand, α, β-AP produced in a small amount from F-α, β-APM by removing the formyl group which is an amino protecting group by using gla-AcOH or acetic acid without using MeOH in aqueous hydrochloric acid solution was crystallized to α-APM hydrochloride. It is converted into α-APM hydrochloride by adding a certain amount of MeOH at the time. That is, after removing the formyl group, methanol was added to the reaction solution in an amount of about 10-100% (v / w) based on 1 mol (322 g) of N-formyl-α, β-L-aspartyl-L-phenylalanine methyl ester. Α-AP is esterified and precipitated as crystals in the form of α-APM hydrochloride while slowly cooling and crystallizing, and then β-AP is β-APM hydrochloride. It is converted and again isomerized to α-APM hydrochloride by acetic acid. At this time, in order to sufficiently process the esterification of α, β-AP by MeOH and the isomerization of β-APM by acetic acid, the temperature is gradually lowered, and then stirred at 10 ° C. to 0 ° C. for 12 to 148 hours. It is possible to prepare α-APM hydrochloride in high yield.

본 발명을 실시예로서 상세히 설명하면 다음과 같다.The present invention will be described in detail as examples.

실시예 1.Example 1.

N-포밀-α,β-아스파탐(322g, 1.0몰 α:β=5:1)에 농염산(35%) 139ml와 물 150ml를 가한 후에 빙초산 32ml를 가하여 50℃에서 1시간 동안 반응시켜 포밀기를 제거한 후, 40℃로 온도를 내린 다음 MeOH 64ml를 가하여 40℃에서 1시간 동안 반응시킨 후 서서히 온도를 내리면서 하루동안 교반시킨 후 5℃가 되게 하였다.139 ml of concentrated hydrochloric acid (35%) and 150 ml of water were added to N-formyl-α, β-aspartame (322g, 1.0 mol α: β = 5: 1), followed by 32 ml of glacial acetic acid and reacted at 50 ° C for 1 hour. After the removal, the temperature was lowered to 40 ° C. and 64 mL of MeOH was added thereto, followed by reaction at 40 ° C. for 1 hour, followed by stirring for 1 day while gradually lowering the temperature to 5 ° C.

석출된 결정을 여과하여 얻은 α-APM·HCl·2H₂O는 316.3g이고, 수율은 86.2%이었다.The α-APM.HCl.2H ₂ O obtained by filtration of the precipitated crystals was 316.3 g, and the yield was 86.2%.

실시예 2.Example 2.

N-포밀-α,β-아스파탐(322g, 1.0몰 α:β=5:1)에 농염산(35%) 70ml와 물 155ml를 가한 후에 빙초산 32ml를 가하여 45℃에서 1.5시간 동안 반응시켜 포밀기를 제거한 후, 40℃로 온도를 내려 농염산 70ml과 MeOH 64ml를 가하여 1시간 동안 교반후 서서히 온도를 내리면서 2인간 교반하여 0℃가 되게 하였다.70 ml of concentrated hydrochloric acid (35%) and 155 ml of water were added to N-formyl-α, β-aspartame (322g, 1.0 mol α: β = 5: 1), followed by 32 ml of glacial acetic acid and reacted at 45 ° C. for 1.5 hours. After removing the mixture, the temperature was lowered to 40 ° C. and 70 ml of concentrated hydrochloric acid and 64 ml of MeOH were added thereto, followed by stirring for 1 hour, followed by gradually stirring the temperature to 2 ° C., to 0 ° C.

석출된 결정을 여과하여 얻은 α-APM·HCl·2H₂O는 314.5g이고, 수율은 85.7%이었다.The α-APM.HCl.2H ₂ O obtained by filtration of the precipitated crystals was 314.5 g, and the yield was 85.7%.

실시예 3.Example 3.

실시예 1과 동일한 조건으로 5∼10℃에서 5일간 교반시켜 얻은 α-APM·HCl·2H₂O는 322.2g이고 수율은 87.8%이었다.Example 1 and was stirred for 5 days at the same conditions 5~10 ℃ _{α-APM · HCl · 2H 2} O obtained was 322.2g and the yield was 87.8%.

실시예 4.Example 4.

실시예 2와 동일한 조건으로 5∼10℃에서 5일간 교반시켜 얻은 α-APM·HCl·2H₂O는 327.4g이고 수율은 89.2%이었다.Example 2 under the same conditions as in 5~10 ℃ was stirred 5 days _{α-APM · HCl · 2H 2} O obtained was 327.4g and the yield was 89.2%.

실시예 5.Example 5.

실시예 2와 동일한 조건으로 5∼10℃에서 7일간 교반시켜 얻은 α-APM·HCl·2H₂O는 325.5G이고 수율은 88.7%이었다.Example 2 under the same conditions as in 5~10 ℃ α-APM · HCl · 2H 2 O obtained by stirring 7-day 325.5G, and the yield was 88.7%.

실시예 6.Example 6.

N-포밀-α,β-아스파탐(322g, 1.0몰 α:β=5:1)에 농염산 140ml과 물 155ml를 가한 용액에 빙초산 64ml를 가하여 60℃에서 30분간 반응하시켜 포밀기를 제거하고 MeOH 64ml를 첨가한 후 5∼10℃에서 5일간 교반시켜 얻은 α-APM·HCl·2H₂O는 324.1g이고, 수율은 88.3%이었다.To a solution of 140 ml of concentrated hydrochloric acid and 155 ml of water was added to N-formyl-α, β-aspartame (322g, 1.0 mol α: β = 5: 1), 64 ml of glacial acetic acid was added and reacted at 60 ° C. for 30 minutes to remove formyl group. After adding 64 ml of MeOH and stirring for 5 days at 5 to 10 ° C., α-APM.HCl.2H ₂ O was 324.1 g and the yield was 88.3%.

실시예 7.Example 7.

실시예 6과 동일하며, 탈보호후 MeOH 64ml를 첨가하여 30℃에서 하루동안 교반한 뒤 7일동안 5∼10℃에서 교반하여 얻은 α-APM·HCl·2H₂O는 316.4g이고, 수율은 86.2%이었다.As in Example 6, after deprotection, 64 ml of MeOH was added thereto, followed by stirring at 30 ° C. for one day, followed by stirring at 5 to 10 ° C. for 7 days, to yield α-APM · HCl · 2H ₂ O, which is 316.4 g. 86.2%.

Claims

A process for preparing α-L-aspartyl-L-phenylalanine methylester hydrochloride from N-formyl-α, β-L-aspartyl-L-phenylalanine methylester, the steps of (a)-(c): (a) reacting N-formyl-α, β-L-aspartyl-L-phenylalanine methylester with glacial acetic acid in an aqueous hydrochloric acid solution to remove formyl groups from the compound; (b) adding methanol to the reaction solution obtained in step (a) and stirring for 0.5-2 hours at a temperature in the range of 30-45 ° C .; And (c) adjusting the temperature of the reaction solution to a range of 0-10 ° C. while stirring the reaction solution for 12-148 hours to precipitate crystals of α-L-aspartyl-L-phenylalanine methylester hydrochloride. Method for producing α-L-aspartyl-L-phenylalanine methyl ester hydrochloride, characterized in that.

The aqueous hydrochloric acid solution added to N-formyl-α, β-L-aspartyl-L-phenylalanine methyl ester in step (a) is N-formyl-α, β-L-aspartyl-L. -Concentrated hydrochloric acid (35%) 30-100% (v / w) and water 30-200% (v / w) with respect to 1 mol of phenylalanine methyl ester.

The amount of glacial acetic acid added in the step (a) is 5 to 100% (v / w) in terms of pure acetic acid based on 1 mole of N-formyl-α, β-L-aspartyl-phenylalanine methyl ester. Method for producing a quantity characterized in that the use.

The amount of methanol added in the step (b) is 10 to 100% (v / w) based on 1 mole of N-formyl-α, β-L-aspartyl-L-phenylalanine methyl ester. The manufacturing method to make.