722 results about "Protecting group" patented technology

The present invention provides a method for synthesizing alacastran, comprising reacting an amino compound of formula V with a chiral intermediate of formula VI, reducing the resulting product with a reducing agent capable of providing an ethyl group to produce a compound of formula VII, and then deprotecting the compound to obtain alacastran, as shown in the following reaction formula. The method for synthesizing alacastran of the present invention avoids the low yield caused by amide reduction and the risk of substrate racemization, has a high yield, low material cost, safe operation, and is suitable for industrial production.

The invention relates to a method for preparing a nerofloxacin chiral piperidylamine intermediate, which comprises the following steps of: carrying out condensation reaction on 5-hydroxy nicotinic acid which is simple and easy to obtain and is used as a raw material and different alcohols, screening through a series of asymmetric catalytic hydrogenation conditions to obtain optimal reaction conditions, and under the conditions, carrying out reaction on various 3, 3 '-dihydroxy nicotinic acid and 3, 3'-dihydroxy nicotinic acid to obtain the nerofloxacin chiral piperidylamine intermediate. The 2, 5-disubstituted pyridine quaternary ammonium salt is reduced into a tetrahydropyridine product, and the C5 site enantioselectivity of the product is excellent. The preparation method comprises the following steps: selecting methyl (R)-1-benzyl-5-hydroxy-1, 4, 5, 6-tetrahydropyridine-3-carboxylic acid methyl ester as a substrate, completely hydrogenating by using platinum dioxide hydrogen, and then carrying out methyl ester reduction, dehydroxylation, Mitsunobu reaction and protecting group removal to obtain a key chiral intermediate for industrial synthesis of a quinolone antibacterial drug nemonofloxacin with high enantioselectivity and high yield.

The invention belongs to the technical field of polymer synthetic materials, and particularly relates to bio-based MS resin and a preparation method thereof. The bio-based MS resin is a free radical copolymer of a methyl methacrylate monomer and a styrene monomer; the methyl methacrylate monomers comprise bio-based methyl methacrylate, isobornyl methacrylate and 3-pinane methacrylate, and the methyl methacrylate monomers comprise methyl methacrylate, isobornyl methacrylate and 3-pinane methacrylate; the styrene monomers comprise styrene and caffeic acid derivatives; based on 100% of the mass of the bio-based MS resin, the methacrylate monomer accounts for 30%; the molar ratio of caffeic acid derivatives to styrene in the styrene monomers is 1: (1-9). The synthesized bio-based MS resin has the characteristics of greenness and reproducibility, compared with petroleum-based MS resin, the performance of the MS resin can be regulated and controlled by designing a protecting group of a bio-based caffeic acid derivative so as to expand the application range of the MS resin, a specific functional group can be introduced to prepare a functional, advanced and high-performance polymer material, and the MS resin has a good market prospect.

The invention discloses a synthesis method of an insulin analogue, which comprises the following steps of: firstly, obtaining A-chain peptide resin by using a solid-phase synthesis method, constructing a disulfide bond between A6 and A11 on a solid phase, and cracking the A-chain peptide resin by using a cracking solution containing a sulfydryl activator to obtain a peptide chain with an activated sulfydryl group and a protected sulfydryl group; then a solid-phase synthesis method is used for obtaining B-chain peptide resin, Lys side chain protecting groups are removed on a solid phase in a fixed-point mode, side chain fatty acid modification is completed, and a peptide chain with an exposed sulfydryl group and a protected sulfydryl group is obtained after cracking is conducted through a cracking solution; and mixing the products in a solution according to a certain proportion to form a first pair of intermolecular disulfide bonds, and constructing and purifying the last pair of disulfide bonds to obtain the insulin analogue. The method disclosed by the invention has the advantages of convenience in synthesis, low cost, simple process and the like, can be used for research on amino acid mutation of insulin compounds, and has important practical significance on development of insulin drugs.

The present disclosure describes novel reagents and processes for preparing oligonucleotides, which have two or more nucleotides. In one embodiment, the reagent is represented by Formula I. wherein: W is O or NH; R1 is -H or a solid support; R2 is a silyl hydroxyl protecting group or an alloc protecting group, R3 is a nucleoside or a group represented by (II) wherein (III) represents the point of attachment for R3.

The invention discloses a preparation method of alplsutentan and an alplsutentan intermediate, alplsutentan is obtained by taking a compound SM1 as a raw material through a one-step method or a multi-step method, and the multi-step method comprises the following steps: reacting the compound SM1 with a compound SM2 to obtain an intermediate I; reacting the intermediate I with 2-[(5-bromo-2-pyrimidinyl) oxy] ethanol to obtain an intermediate II, or reacting the intermediate I with ethylene glycol to obtain an intermediate I-b, and then reacting with 5-bromo-2-chloropyrimidine or 5-fluoro-2-chloropyrimidine to obtain the intermediate II; and finally, removing a protecting group from the intermediate II to obtain alpoxivan. The one-step method comprises the following steps: when X in a compound SM1 is a fluorine atom, the compound SM1 is 5-(4-bromophenyl)-4, 6-difluoropyrimidine, and the compound SM1 reacts with sulfonamide and 2-[(5-bromo-2-pyrimidinyl) oxy] ethanol to directly obtain alpoxivan. The synthesis route is short, and the reaction conditions are mild.

The present invention relates to the field of drug synthesis, and specifically relates to a method for preparing a Zavegepant intermediate and a derivative thereof. Specifically, the method comprises reacting a compound of formula II with a compound of formula III to obtain a compound of formula I, reacting the compound of formula I with isoamyl nitrite to obtain compound V, and removing a protecting group from the compound of formula V to obtain a compound of formula VI or a salt thereof. On the basis of the preparation method provided by the present invention, the raw materials are readily available, the production cost is relatively low, there are fewer synthesis steps, and the operation is simpler and more convenient.

The application discloses a PAG bonding type photosensitive photoresist resin and a preparation method and application thereof. The photoresist resin is as follows: formula. The PAG bonding type resin is prepared through the following reaction process: 1) performing a RAFT polymerization reaction on p-acetoxystyrene, p-styrene sulfonamide trifluoromethyl potassium salt and a RAFT chain transfer agent under the action of an initiator to obtain an intermediate I, 2) performing a hydrolysis reaction on the intermediate I to obtain an intermediate II, 3) performing a protection group introduction reaction on the intermediate II and di-tert-butyl dicarbonate to obtain an intermediate III; and 4) performing an ion exchange reaction on the intermediate III and triphenylsulfonium bromide. The application realizes the bonding of the PAG into the resin skeleton, and improves the problems of poor compatibility between the PAG and the resin, phase separation, uneven distribution of the PAG and the like. Therefore, the photoresist prepared from the resin has the photo-generated acid bound by the polymer main chain and limited diffusion, the resolution is improved, and the photoetching effect is excellent.

The invention provides a synthesis method of tilpotide, which comprises the following steps: dividing a target peptide chain into six fragments, and adopting bis (4-C18-C28 alkoxy phenyl) methylamine, 2, 4-bis (18-C28 alkoxy)-benzyl alcohol and NH2-Asp (OTAG)-OR1 as hydrophobic label carriers to assist synthesis. A side chain carboxyl group of aspartic acid is innovatively used as an anchoring position of a hydrophobic label, a new fragment connection route is designed, a full-protection tilpotide conjugate is synthesized through a multi-label synergistic effect, and finally a protecting group and a label are removed by using a TFA lysate. Compared with a solid-phase synthesis method, the method is carried out in a homogeneous reaction, the dosage of amino acid and the condensing agent is reduced to 1-1.2 times from 2-3 times, and the cost is remarkably reduced. Compared with an existing hydrophobic labeling method, the method has the advantages that multiple labels can be introduced to serve as protecting groups, the yield and purity of synthesis of medium-chain and long-chain polypeptides are improved, meanwhile, the problem of hydrophobicity attenuation caused by peptide chain extension is solved, and the green chemical process requirement is met.

The invention discloses a synthesis process of chiral cyclic ether indole. The synthesis process comprises the following steps: reacting 4-bromobenzaldehyde with malonic acid under the catalysis of piperidine to generate olefin carboxylic acid CHP-1; carrying out condensation reaction to prepare CHP-2; under the catalysis of a copper reagent, carrying out Michael addition reaction to obtain CHP-3; preparing a chiral alcohol intermediate CHP-4 through a reduction reaction; trifluoromethanesulfonic acid is used, and a chiral ether intermediate CHP-5 is prepared through ring closing; reacting with protected hydrazine by using a copper ion catalyst to obtain an intermediate CHP-6; the method comprises the following steps: by taking alcohol as a solvent, adding strong acid, and removing a protecting group of hydrazine to obtain an intermediate CHP-7; and carrying out ring closing by taking lewis acid as a catalyst to obtain an indole product CHP-8. The use of a noble metal catalyst palladium is avoided, and the cost is greatly reduced. The chiral center is directly constructed through a chemical method, and SFC is not needed for resolution, so that the cost is remarkably reduced, and industrial production is successfully realized.

The invention discloses a preparation method of protecting group cefdil side chain acid. The preparation method comprises the following reaction steps: step 1, performing oximation reaction on a compound IV to obtain a compound V; 2, cyclizing the compound V and thiourea to obtain a compound VI; 3, condensing the compound VI and tert-butyl alpha-bromoisobutyrate to obtain a compound VII; 4, the compound VII passes through a protective group to obtain a compound VIII; and 5, hydrolyzing the compound VIII to obtain the product protecting group cefdil side chain acid. The raw materials used in the method are simple and easy to obtain, expensive reagents and customized raw and auxiliary materials are not used, the process operation is simple, a major dangerous process is not involved, and the method has industrial advantages.

Provided is a method for producing a protected glycoside derivative, including reacting a sugar in which all hydroxyl groups of the sugar are protected by protective groups and protective groups of a hydroxyl group at a 1-position and a hydroxyl group at a 2-position are acyl groups, with a phenolic compound in the presence of at least one catalyst selected from the group consisting of trifluoromethanesulfonic acid and copper (II) trifluoromethanesulfonate, in which the phenolic compound is bonded to an anomeric position of the sugar and other hydroxyl groups of the sugar are protected.

The invention relates to the technical field of compound synthesis, in particular to an intermediate of gepodalin, a preparation method of the intermediate and a preparation method of gepodalin. The intermediate of gepodamycin is selected from any one of compounds shown in the following structural formula, and in the formula, X represents halogen, and R1 represents a hydroxyl protecting group; r2 represents an amino protecting group, and R3 represents a C1-C10 alkyl group. The intermediate can be synthesized to obtain the core intermediate of gepodamycin through a series of new synthesis steps, and the yield, the purity and the post-treatment difficulty of the core intermediate can be improved, so that the production cost of gepodamycin is greatly reduced.

The invention discloses an oligonucleotide synthesis process of a sulfo-PMO structure. In the oligonucleotide synthesis process of the sulfo-PMO structure, the molecular structural formula of sulfo-PMO is shown in the specification. According to the invention, the molecular structure of thio-PMO is specifically limited, and the synthesis of nucleotide phosphate amide and (thio) phosphoric acid amide in the solid-phase synthesis oligonucleotide is carried out along the direction from 5'to 3 ', that is, in each cycle period, the O5'or O6' position of the nucleotide phosphate amide and (thio) phosphoric acid amide monomer is firstly subjected to coupling reaction, and then the protecting group is removed at the O3 'or N3' position, so that the oligonucleotide phosphate amide and (thio) phosphoric acid amide are obtained. And releasing active hydroxyl or amino / amido to enter the next cycle. The protecting group adopted by the sulfo-PMO molecule is consistent with the protecting groups of other nucleotides, so that the conversion rate of each step of coupling reaction can be conveniently detected on line.

The application provides a novel preparation method of maraviroc, which forms a stable intermediate by protecting phenolic hydroxyl with n-pentyl, so that the condensation with (R)-(+)-tetrahydrofuran-2-formyl chloride has a high yield, and the by-products generated by removing the protecting group in the reaction process are reduced; the use of the controlled reagent 1-propyl phosphonic anhydride in the condensation of (R)-(+)-tetrahydrofuran-2-formic acid in the original process is eliminated. In the subsequent docking with the C fragment, by adjusting the polarity of the solvent, the product is easily precipitated, the conversion rate is improved, and the product is easy to separate and purify, so that the problem of low conversion rate of the protecting group reported in the literature is solved. The improved method has the advantages of simple reaction and operation, easy impurity removal, and a reaction yield increased by about 10% compared with the previous method, and is an industrialized amplification implementation feasible process.

The invention discloses a chemical-enzymatic coupling synthesis method of oseltamivir phosphate, which comprises the following steps: by taking monasic acid OS-01 as a substrate, sequentially carrying out S1 esterification, S2 ketalation, S3 selective ring opening, S4 TEMPO oxidation, S5 primary transaminase reaction, S6 acetylation, S7 secondary transaminase reaction and S8 phosphorylation reaction to obtain the final product oseltamivir phosphate OS-09. According to the method, the step of sodium azide required by a traditional route is avoided, the production safety and the industrialization possibility are enhanced, two different transaminases are used for respectively constructing different chiral centers, the steps of protecting groups and deprotecting groups on the traditional route are not needed, the overall route is short, the used chemical reagents are few, the yield is high, and the method is suitable for industrial production. The industrial requirements of environmental protection and low cost are met.

The invention provides a method for synthesizing N-methylated polypeptide, which comprises the following steps: dissolving a carboxylic acid compound, N-methyl amino-acid ester hydrochloride or N-methyl amino-acid ester, an alkaline substance and pivaloic anhydride in an organic solvent, reacting at 15-80 DEG C for 3-10 hours, and post-treating the obtained reaction liquid to obtain an N-methyl dipeptide compound, the method comprises the following steps: removing a protecting group in an N-methyl dipeptide compound to obtain a free-state N-methyl dipeptide compound, and condensing the free-state N-methyl dipeptide compound and amino acid or N-methyl amino-acid ester protected by amino to obtain the N-methylated polypeptide, the mixed anhydride intermediate is formed in situ, and the reaction is completed in one step; according to the method, trimethylacetic anhydride is used as a condensing agent, the structure is simple, the reaction is safe, cheap and non-toxic, a large amount of nitrogen-containing byproducts are not generated in the reaction, and purification is convenient; the method is high in stereoselectivity, and racemization is avoided; according to the method, environment-friendly solvents such as ethyl acetate can be used, the reaction condition is mild, and the reaction time is short.

The invention relates to the technical field of high polymer materials, and discloses a solvent-resistant polyurethane composite material and a preparation method thereof, and the material is prepared by reacting the following components: an isocyanate component, a polyol component and a functional chain extender component; the functional chain extender is a derivative of ortho-amino aromatic carboxylic acid protected by a thermally unstable ester group, and the protecting group is decomposed under a thermal treatment condition and releases a functional group in situ, wherein the functional group can be subjected to cyclization reaction with ureido on a polymer chain to form a heterocyclic cross-linked structure; the preparation method comprises the following steps: (a) reacting an isocyanate component, a polyol component and a functional chain extender to obtain a soluble and processable linear polyurethane precursor; and (b) carrying out high-temperature heat treatment on the molded precursor. Through the design of the latent functional group and the two-step process, the contradiction between the processability and the final performance of the cross-linked polyurethane is solved, and the prepared material has excellent solvent resistance, thermal stability and good mechanical properties.

The invention discloses N-alkylated / sulfonated benzimidazole polyaryletherketone / polyaryletherketone sulfone with controllable grafting density as well as a preparation method and application of the N-alkylated / sulfonated benzimidazole polyaryletherketone / polyaryletherketone sulfone. The preparation method comprises the following steps: firstly, introducing a protecting group on a phenolic hydroxyl group of a bisphenol monomer containing a benzimidazole structure, then carrying out nucleophilic substitution reaction on alkyl halide / alkyl halide sulfonic acid and-NH, and then removing the protecting group to obtain an N-alkylated / sulfonated benzimidazole functionalized bisphenol monomer; copolymerizing the monomer, a bisphenol monomer and a difluoro monomer to obtain a polymer; alkyl or alkyl sulfonic acid is introduced to a benzimidazole ring, so that-NH bonds are passivated, a steric hindrance effect is formed, and gelation of the polymer under a high polymerization degree is avoided; by adjusting the molar ratio of the monomers, the retention stability of the functional groups can be effectively controlled, and compared with the traditional grafting on the polymer, the non-regulation of functionalization and the gelation of the polymer are effectively avoided.

The application provides a method for synthesizing triaminotriphenylmethane, which does not need to use a solvent, uses N,N'-dibenzylaniline and trialkoxymethane as synthetic raw materials, and makes N,N'-dibenzylaniline and trialkoxymethane undergo a Friedel-Crafts alkylation reaction, so as to avoid the generation of 2,4',4"-triaminotriphenylmethane isomers in a traditional synthesis method by using the steric effect of two benzyl protective groups, thereby obtaining 4,4',4"-tri(N,N'-dibenzylaminophenyl)methane with high selectivity. 4,4',4"-tri(N,N'-dibenzylaminophenyl)methane is further subjected to a debenzylation reaction under neutral conditions to form triaminotriphenylmethane. According to the chemical structural formula of the target product, the benzyl group as the protective group of the amino group is reduced under a neutral environment, and the benzyl group is removed, and the formed byproduct is only toluene, which not only ensures the high yield and high selectivity of the target product, but also is very beneficial to obtaining high-purity 4,4',4"-triaminotriphenylmethane, and conforms to the principle of green chemistry.

The application relates to a synthesis method of an anti-freezing glycopeptide polypeptide and belongs to the technical field of polypeptide drug synthesis. The method comprises the following steps: 2-CL-Resin is used as a carrier resin, under the condition of adding an activating agent, the carrier resin and alanine are coupled to obtain Fmoc-Ala-2-CL-Resin; according to the amino acid sequence of the anti-freezing glycopeptide, other amino acids are sequentially coupled through a solid-phase synthesis method; after a protecting group is removed and the carrier resin is cleaved, the anti-freezing glycopeptide crude peptide is obtained; and after purification, salt conversion and freeze-drying, the anti-freezing glycopeptide polypeptide is obtained. The method has the advantages of short synthesis period, low cost, easy post-treatment, few by-products, high product yield, facilitation of large-scale production of the anti-freezing glycopeptide, and considerable economic applicative value and wide application prospect.

A light-emitting device comprising a light-emitting layer between a pair of electrodes, wherein the light-emitting layer contains a first material, a second material and a third material, wherein the first material can convert the triplet excitation energy into light emission and has a five-membered ring framework, wherein the first material is a metal complex, wherein the second material can convert the singlet excitation energy into light emission and has a luminophore and five or more protecting groups, wherein the luminophore is a condensed aromatic ring or a condensed heteroaromatic ring, wherein the five or more protecting groups each independently comprise an alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms or a trialkylsilyl group having 3 to 12 carbon atoms, wherein the third material comprises a diazine framework or a triazine framework, and wherein a T1 level of the first material is higher than an S1 level of the second material.

The present invention provides a method for producing a compound represented by formula (I) suitable for mass synthesis as API. Provided according to one aspect of the present invention is a method for producing a compound represented by formula (I) or a salt thereof, the method including deprotecting a protecting group represented by R1 in formula (II) under basic conditions to thereby form a compound represented by formula (I) or a salt thereof.

The invention relates to an anti-epileptic polypeptide coupling medicine and a preparation method and application thereof, the polypeptide coupling medicine comprises an Fmoc protecting group, a permeation accelerating peptide and a cell penetrating peptide which are sequentially connected from the N end to the C end, and the permeation accelerating peptide is connected with an anti-epileptic medicine molecule. According to the invention, by fully utilizing the treatment requirements of epileptic seizure and the technical advantages of intranasal drug delivery, through the collaborative design of the protecting group, the functional polypeptide sequence and the anti-epileptic drug, the defects of poor brain targeting property, easy cyclization of a polypeptide carrier, low intranasal delivery efficiency and the like of the traditional anti-epileptic drug are overcome, non-invasive, efficient and low-toxicity epilepsy treatment is realized, and the application prospect is wide. And the preparation process is simplified, the clinical transformation requirement is met, and meanwhile, a new strategy is provided for non-invasive brain delivery of neuropeptide drugs.

Encoded separation pool libraries are provided herein, which are useful, inter alia, in forming highly diverse and dense arrays for screening and detecting a variety of molecules. A method of immobilizing a microparticle on a solid support is disclosed, wherein the microparticle is covalently linked via first and second linkers to a linker domain (e.g., peptide, protein, small molecule) and a nucleic acid, and performing a decoding process on the nucleic acid domain, thereby determining the composition of the linker domain and its location on said solid support. The second linker is selectively cleavable provided that the first linker is not cleavable. The decoding may include hybridization or sequencing. The second linker is e.g. a photocleavable linker or includes -S(O)2NH- -NHS(O)2- -C(O)O-, -OC(O)-, -C(O)NH-, -NHC(O)-.The linker domain may be bound to a linker ligand (which may be fluorescent), unless protected by a protecting group, which may be removed.

The invention discloses a synthesis method of 5-nitro-2-aminophenol, which comprises the following steps: by using 2-chloro-4-nitroaniline as a raw material, providing an amino protecting group by using di-tert-butyl dicarbonate ester to obtain a compound 3; carrying out hydrolysis reaction in an alkaline environment to hydrolyze chlorine groups on benzene rings into hydroxyl groups to obtain a compound 4; and removing an amino protecting group under an acidic condition to obtain the 5-nitro-2-aminophenol. According to the method, 2-chloro-4-nitroaniline is used as a starting raw material, compared with expensive ortho-aminophenol, the cost of the raw material can be remarkably reduced, use of expensive catalysts in the hydrolysis process is avoided through amino protection, generation of the byproduct 2-amino-4-nitrophenol is effectively reduced, and the yield of the 2-chloro-4-nitrophenol is increased. And the synthesized 5-nitro-2-aminophenol has relatively high purity (99.5%) and relatively high yield (-86%). The method has the advantages of conventional production steps and conventional process equipment, and has a good application prospect.

This application discloses a linker and its preparation method. The linker includes pharmacophore P, pharmacophore Q, and deoxynucleotides and / or deoxynucleotide derivatives connecting pharmacophore P and pharmacophore Q. Pharmacophore P is obtained by removing the protecting group from group B, and pharmacophore Q is obtained by removing the protecting group from group X. Group B is obtained by chemically modifying the benzylquinolone carboxylic acid pharmacophore, and group X is obtained by chemically modifying the zenomeprazole pharmacophore. The linker is prepared by linking group B and group X with deoxynucleotides and / or deoxynucleotide derivatives to form the linker, including solid-phase synthesis technology. The method of this application can automatically synthesize molecular probes or bivalent drugs containing two pharmacophores, thereby replacing the traditional stepwise linking method, enabling efficient construction of screening libraries, and allowing control of the spatial distance and spatial orientation of the pharmacophores by adjusting the number and base arrangement of deoxynucleotides.

The invention discloses a high-yield method for reducing dinitro and retaining sensitive protecting groups, which comprises the following steps: adding water, sodium dithionite and sodium carbonate into a container, stirring and clarifying, and dropwise adding a mixed solution containing raw materials; after the reaction is finished, extracting, separating liquid, concentrating, and purifying by silica gel column chromatography to obtain a product and a byproduct; the raw material is a compound containing a carbon-carbon double bond, a p-methoxybenzyl protecting group, a t-butyloxycarboryl protecting group and dinitro. Adding a byproduct into a phosphoric acid mixed solution for reaction; and after the reaction is finished, adding dichloromethane and water, dropwise adding triethylamine to adjust the pH value, extracting, separating liquid, drying, concentrating, and purifying by silica gel column chromatography to obtain the product. According to the method, a sodium hydrosulfite / sodium carbonate system and phosphoric acid step-by-step treatment strategy is adopted, reduction of dinitro is achieved under mild conditions, meanwhile, PMB protecting groups, Boc protecting groups and C-C double bonds are reserved, and the problem that stability and high yield of the protecting groups cannot be considered at the same time in an existing method is solved.

Described is a compound for substituting amino acids of proteins or peptides, wherein the compound has the formula (1)wherein the stereocenter C1* represents CH that either results in the D- or L-form of the compound of formula (1); A− is a negatively charged ion compensating the positive charge; X1 is H or an amine protecting group; X2 is OH, an ester residue or an amide residue or an activated carboxylic acid derivate to be used for the formation of an amide bond; Y1, Y2 and Y3 are independently from each other a C1-C6 alkyl, and Z1 and Z2 are independently from each other a nucleobase, a C1 to C16 alkyl group, an aromatic residue or a heteroaromatic residue, wherein the aromatic residue or the heteroaromatic residue contains one 5, 6, or 7-membered ring or two condensed 5, 6, or 7-membered rings sharing two carbon atoms, wherein the aromatic residue or the heteroaromatic residue can be substituted by a linear or branched C1 to C16 alkyl group and / or a further aromatic group. Furthermore, a method for preparing this compound and proteins and peptides containing this compound are disclosed.

To provide a method for preparing oligonucleotides that can improve yields and purities of target phosphorodiamidate morpholino oligomers and reduce 4-nitrostyrene adduct impurities.SOLUTION: The process comprises: (a) converting a compound of Formula X-1 into a compound of Formula X-2: where R10 is a residue of an oligonucleotide (e.g., a phosphorodiamidate morpholino oligomer); R11 is an amine protecting group; wherein the compound of Formula X-1 is not bound to a solid support; and (b) optionally removing protecting groups in the compound of Formula X-2 to obtain the olignucleotide.SELECTED DRAWING: None