JPS62181269A - Novel active esterification agent compound - Google Patents

Abstract

NEW MATERIAL:Bis(6-trifluoromethylbenzotriazolo)carbonate of formula I. USE:An active esterification agent for producing active ester of an amino acid capable of proceeding peptide synthesis in high yield, an agent for introducing a novel carbonate-type of carbamate-type protective group to hydroxyl group (or amino group) and a reagent for the synthesis of an active carbonate compound or active carbamate compound. PREPARATION:The compound of formula I can be produced by reacting the compound of formula II with the compound of formula III in an organic solvent such as ether. The obtained compound is rapidly reactive with an N-protected amino acid in acetonitrile to form an active ester of an amino acid in high yield. A dipeptide can be produced from the active ester by aminolyzing with another amino acid (protecting carboxylic acid as ester-form) without separating from the former reaction mixture.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention is useful as an esterifying agent for producing various active esters, and especially as an esterifying agent for preparing amino acid active esters that can carry out peptide synthesis with high yield. The present invention relates to a useful novel compound, bis(trifluoromethylbenzotriazolo)carbonate.

(Problems to be solved by conventional technology and invention) Conventionally,
In the synthesis of PeptiP, an active ester method is known in which an amino acid is converted into an active ester and then dehydrated and condensed with other amino acids to produce a peptide. In the synthesis of peptides, in addition to the active ester method described above, acid anhydride methods and azide methods are generally known as methods for activating amino acids that are less likely to cause racemization. The peptide synthesis reaction using the active ester method involves the steps of preparing an active ester of an amino acid, and converting the amino acid active ester to an amine component (an amine group that is dehydrated and condensed with the calxylate group of the active ester to form an amide bond). It consists of two steps: a step of coupling with the amino acid). In peptide synthesis using the active esterification method, active esterification /l/ groups (!: L tehas p-nitrophenyl groups, N-hydroxysuccinimide groups, N-hydroxyphthalimide groups, etc.) and various other groups are used to make amino acids into active forms. It has been known.

Previously, the present inventors used N,N'-disuccinimidyl carbonate: N,N'-diphthalimidyl as an esterifying agent for producing all active esters of amino acids used in peptide synthesis from amino acids. carzene): N, N'-bis(ternorbornene-2,
We have created carbonate compounds such as 3-dicarzeximidyl) carbonate and oxalate compounds such as bis[/-(+-trifluoromethylbenzotriazolo)oxalate, and when these compounds act on amino acids, they induce amino acid activity. The ester can be easily L'Jff in good yield under mild conditions, racemization is unlikely to occur during this preparation, and the amino acid active ester can be condensed with other amino acids (amine components) to form peptide gold. It was discovered that racemization is difficult to occur even when seedlings are harvested (Japanese Patent Application Laid-open No. 11/1989/≠zttz; US Special Proposal No. tA
3μ] No. 707 specification and Japanese Patent Application Laid-Open No. 6O-Itt No. 670).

However, there is a need for the development of a more satisfactory active esterifying agent.

(Means for Solving the Problems) The present inventors further conducted research and discovered that bis[/-(A-trifluoromethylbenzotriazolo)]cacarbonate as a novel red-bonnet-type compound was completely sweetened. succeeded in
It has now been discovered that the compound can be advantageously used as an active esterifying agent for amino acids or other calselic acids, and that a variety of useful active carbonate compounds can be prepared by reacting with various alcohols.

That is, the present invention provides bis(6) of the following formula as a new compound.
-trifluoromethylbenzotriazolo)carbonate.

Bis(4-toIJ fluoromethylbenzotriazolo)carbonate (hereinafter sometimes abbreviated as BTBO) according to the present invention can be used as (a) a peptide synthesis reagent, that is, an amino acid active ester that can proceed with peptide synthesis in good yield. As an active esterification agent for production, (b) as a raw material for the preparation of a new carbonate-type protecting group-introducing agent for hydroxyl groups, or as a raw material for the preparation of a new carbamate-type (urethane-type) protecting group-introducing reagent for amino groups. It is also useful as (c) a reagent for the synthesis of active carbonate compounds and active carbamate compounds.

The above active carbonate derivatives and active carbamate derivatives synthesized using the BTBO'i of the present invention are
Furthermore, the compounds of the invention (
1) can be used in the field of synthesis.

Preparation of the novel compound fl) of the present invention (/-hydroxy-t-(trifluoromethyl)benzotriazole and trichloromethylchloroformate (fill'!r
This is achieved by reacting according to the following reaction formula.

This reaction is suitably carried out in an organic solvent such as ether, and in this reaction, the compound is preferably used in an excess amount, for example 3
Preferably, trichloromethyl chloroformate (lit) is added to the reaction system in an amount of 1:1 molar ratio.

The compound (I) of the present invention, that is, bis(6-toIJ fluoromethylbenzotriazolo) carbonate, has the following properties:
When used in the preparation of active esters of amino acids, N-
When a protected amino acid is reacted with acetotrile in the presence of pyridine, it reacts rapidly and gives an amino acid active ester in good yield. Retains carboxyl group
9) to give a dipeptide. When producing this dipeptide, the following formula (1v
) -trifluoromethylbenzotriazole forms a by-product of /-hydroxy-. The reaction formula for these series of reactions is as follows.

[First amino acid (N-recipient)] (Compound of the present invention) Indicates a hydrogen atom or a residue in an amino acid. R, 'U Indicates an ester-forming group for carboxyl protection.

When the carboxylic acid active ester derived using the novel compound (1) of the present invention is reacted with the amine group of an amino acid, amino rinsing proceeds with good yield at room temperature as described above. On the other hand, when alcoholysis is carried out by reacting the above carboxylic acid active ester with the hydroxyl group of various alcohol compounds in the presence of a base such as triethylamine or dimethylaminopyridine, the transesterification reaction proceeds with good yield at room temperature.

Next, the method for producing the compound of the present invention will be explained with reference to Examples.

110 Preparation of bis<t-trifluoromethylbenzotriazolo)calzenate.

/-Hydroxy-6-(trifluoromethyl)benzotriazole (o,3y<o,i mol) was dissolved in 710-dry ethyl ether. Add 54C of trichloromethyl chloroformate to the solution under stirring at room temperature.
When y (o, o coj moles) was introduced into the solution, the desired compound of the present invention, bis(J-trifluoromethylbenzotriazolo) calzenate, began to precipitate on the edge for several minutes. Stir as it is for 7 hours, then add trichloromethyl chloroformate/
+s7! I then relaxed for about an hour. Filter while hot, wash the crystals with dry ethyl ether,
Dry.

Pure crystals of the title compound were obtained without recrystallization. (Yield 70%).

Melting point/31-/≠3℃ (decomposition) Mass spectrometry value 2M+≠32 Elemental analysis value; Actual value C2≠/, A7 H, 8≠ON,/
, 4Lθ% theoretical value C9≠/, At l(,/, u
r N, /ri, Hiro ≠ Chi NMR (7th cell) 7-d6):
7.60-J, IAJ-(1,11 aromatic)IIL
(I(Br): /100./za/j (Cal Nil)
,/Otsu O! (aromatic).

Next, Reference Example 1 shows an example of the preparation of an amino acid active ester and the synthesis of a dipeptide using the compound of the present invention, bis(6-trifluoromethylbenzotriazolo) calzenate (hereinafter abbreviated as BTBO).

Synthesis of Kou Ajo bipenzyloxycarbonylalanylglycine ethyl ester (Z-Ata-GlyOEt). 21jttpg of N-benzyloxycarbonylalanine (/
7 mmol) and B'l'BO (7 mmol) were suspended in acetonitrile, and 7 mmol (/7 mmol) of pyridine was added with stirring. After 3 hours of reaction (check the completion of the reaction using thin layer chromatography), an amine component was added to the reaction solution containing the produced 6-dolifluoromethylbenzotriazoloester of 7'cr'J-benzyloxycarbonylalanine. /≠OIIF/ (/ mmol) of glycine ethyl ester hydrochloride and 10/q (/ mmol) of triethylamine (acetonyl)
IJ Al solution (total Q/me) was added. After reacting for g hours (the completion of the reaction was thoroughly checked using thin layer chromatography), the core liquid was treated in a conventional manner to obtain the title compound. Yield is Ochi.

Melting point Tatar 100'C [α), 22-. 22. o0cc=/, x ta/
-R) Next, the active Cal is reacted with the hydroxyl group of the BTBC'i alcohol compound of the present invention through a transesterification reaction. A reaction example for synthesizing Neto-6 is shown as Reference Example 2.

Synthesis of nate compounds.

BTBO ≠ 32■ (769 mol) total acetonitrile i
Suspended in oo, 1, and 101~(
769 mol) Full power [1] The transesterification reaction was carried out by stirring at room temperature. After reacting for about 2θ hours (check the reaction rate using thin layer chromatography), the solvent is distilled off, and the remaining amount is ≠
Sodium bicarbonate was added to dissolve the reaction by-product 7-hyProxy&-trifluoromethyl4-IJ azole. The solid residue in the injected mixture was separated, and the P solution was dried and recrystallized from acetone-ether to obtain the compound described above. yield ! J 4'% Mass spectrometry: M+337 Melting point: I63-/j! °C Elemental analysis value: Actual value 0! , 3. /riH2,ri,2
N I2. ! ≠Theoretical value Q! 3. ≠211 J,
Rit N I2. ≠j% As shown in the above reference example λ, the ester conversion reaction using BTBOi can be used as a new method for introducing a carbonate-type protecting group into the hydroxyl group of an amino acid or a natural substance, instead of the existing protecting group introduction method.

Next, when the active lugeneate compound obtained by transesterifying the compound of the present invention (BTBC) with an alcohol compound is reacted with the amino group of an amine compound, a urethane compound is produced. Indicated by 3.

15 liters leftover Reaction of active force ruzenate and amine.

COOOH.

Compound (3) (1v) For a solution of 370 μm (1 mol) of active car7zenate compound (1) represented by the above formula in acetonitrile (.20 m7), the compound represented by the above formula (λ ), i.e. Nonorin methyl ester hydrochloride (Vat-OMe
Fist HC4)/Otsu7. Ouq (/ mmol) and
A solution of triethylamine 10/lq (769 mol) in acetonitrile (Zmt) was added and stirred at room temperature. Completion of the reaction was checked by thin layer chromatography, and the reaction solution was treated in a conventional manner. Compound (3) represented by the above formula,
f, ie, N-penzyloxycarzenylp+J7.methyl ester (Z-Vat-00H3) was obtained. Yield: 5%.

(a) D-I7.7° (cl, /, ethanol) jH-
NMR (δ) = 7.27 (jH, 8, 06H5),
j, O-1'(2H, S.

PhC) I2) ≠, λ2 (jH, 4', jHz, q, NHO) (),
O, PO(j)(.

≠Hz g q , (Me)2 The active carbonate compound obtained by transesterifying the compound of the present invention (BTBO) with an alcohol compound is
An example of a reaction in which a second carbonate compound is produced by transesterification when further reacted with another alcohol compound is shown below in Reference Example≠.

Reference example ≠ Reaction of active luzenate and alcohol (IV) 3 of active luzenate compound (1) shown by the above formula
70 tη (/, l mmol) of tetrahydrofuran (
In a THF) solution, an alcohol compound of the above formula (Hiro), namely furfuryl alcoholta f, /In9 (/mi IJ
mole] and gauge methylaminopyridine (DMAP)/2
Corrq (1 mmol) was added and the mixture was stirred at room temperature.

Completion of the reaction was checked by thin layer chromatography, and then the reaction solution was treated by a conventional method to obtain carbonate compound II) represented by the above formula.

Yield: 5% (Effects of the Invention) The compound of the present invention (BTBC!, 1) is an excellent active esterifying agent for amino acids and is advantageously used in peptide synthesis, and is also a novel calzenate-type protecting group-introducing agent for hydroxyl groups. It can also be used as a novel protective group-introducing agent for amine groups, and can also be used as a raw material for preparing a protective group-introducing agent, making it useful in various synthetic fields.

Claims (1)

[Scope of Claims] Bis(6-trifluoromethylbenzotriazolo) carbonate represented by the following formula ▲ Numerical formulas, chemical formulas, tables, etc. are available ▼.