# US 12,760,307 B2 · Morpholino oligonucleotide derivatives

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- Number: US 12,760,307 B2
- Document ID: US12760307B2
- Status: Granted
- Kind: B2
- Application number: 18/007,830
- Filed: 2021-06-07
- Published: 2023-07-27
- Granted: 2026-10-13
- Earliest claimed: 2020-06-05
- Assignees: Nexoligo Co., Ltd.
- Applicants: Nexoligo Co., Ltd.
- Inventors: Yeohong Yoon
- Web page: https://patentgrep.com/patent/US12760307B2

## CPC

- C12N 15/113: Non-coding nucleic acids modulating the expression of genes, e.g. antisense oligonucleotides; {Antisense DNA or RNA; Triplex- forming oligonucleotides; Catalytic nucleic acids, e.g. ribozymes; Nucleic acids used in co-suppression or gene silencing (when used in plants C12N15/8218)}
- C07F 9/6561: containing systems of two or more relevant hetero rings condensed among themselves or condensed with a common carbocyclic ring or ring system, with or without other non-condensed hetero rings
- C12N 2310/3233: Morpholino-type ring
- C12N: MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA (microbiological testing media C12Q1/00)
- C07F: ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM (metal-containing porphyrins C07D487/22)

## Abstract

The present invention relates to a novel morpholino oligonucleotide comprising at least one type of morpholino nucleotide monomer having pyrrolocytosine (pC) among unnatural cytosines, and relates to a morpholino oligonucleotide capable of more selectively binding to a target RNA and exhibiting excellent cell penetration compared to an MPO having a natural cytosine, and thus being capable of greatly contributing to the development of a therapeutic agent for incurable diseases in the area of morpholino oligonucleotides.

## Claims

### Claim 1

A morpholino nucleotide monomer substituted with pyrrolocytosine of the following Chemical Formula 6:
wherein:
PG3 is selected from the group consisting of fluorenylmethoxycarbonyl (Fmoc), 1,1-dioxobenzo[b]thiophen-2-ylmethoxycarbonyl (Bsmoc), 2-(4-nitrophenylsulfonyl)ethoxycarbonyl (Nsc), 2-(4-sulfophenylsulfonyl)ethoxycarbonyl (Sps), ethanesulfonylethoxycarbonyl (Esc), phthaloyl, tetrachlorophthaloyl (TCP), 2-fluoro fluorenylmethoxycarbonyl (Fmoc (2F)) and 2,7-ditert-butyl fluorenylmethoxycarbonyl (DtBFmoc);
PG4 is selected from the group consisting of tert-butoxycarbonyl (Boc), trityl (Trt), α,α-dimethyl-3,5-dimethylbenzyloxycarbonyl (Ddz), 2-(4-biphenyl) isopropoxycarbonyl (Bpoc) and 2-nitrophenylsulfenyl (Nps);
x is an integer of 1 to 3; and
y is an integer of 1 to 3.

### Claim 2 (depends on 1)

The morpholino nucleotide monomer according to claim 1 wherein:
the morpholinonucleotide monomer substituted with pyrrolocytosine of Chemical Formula 6 is represented by a structure selected from the group consisting of the following Chemical Formulas 6-1, 6-2 and 6-3: