US 11,897,914 B2
Synthesis of 2′ protected nucleosides
Wing C. Poon, Union City, CA (US); Ruiming Zou, Union City, CA (US); Aldrich N. K. Lau, Palo Alto, CA (US); David Yu, Union City, CA (US); Gengyu Du, Union City, CA (US); Yun-Chiao Yao, Union City, CA (US); and Gang Zhao, Union City, CA (US)
Assigned to Hongene Biotech Corporation, Union City, CA (US)
Filed by Hongene Biotech Corporation, Union City, CA (US)
Filed on Nov. 28, 2022, as Appl. No. 18/059,357.
Claims priority of provisional application 63/283,945, filed on Nov. 29, 2021.
Prior Publication US 2023/0416295 A1, Dec. 28, 2023
Int. Cl. C07H 21/02 (2006.01); C07H 19/10 (2006.01); C07H 19/067 (2006.01); C07H 19/167 (2006.01); C07H 19/20 (2006.01); C07H 23/00 (2006.01)
CPC C07H 21/02 (2013.01) [C07H 19/067 (2013.01); C07H 19/10 (2013.01); C07H 19/167 (2013.01); C07H 19/20 (2013.01); C07H 23/00 (2013.01)] 23 Claims
 
1. A compound of Formula (I):

OG Complex Work Unit Chemistry
or a pharmaceutically acceptable salt thereof,
wherein
R1 is hydrogen or a hydroxy protecting group;
R2 is hydrogen, a hydroxy protecting group, —C(═O)CH2CH2C(═O)R3, or —P(OR4)NR5R6;
alternatively, R1 and R2 are joined together to form a 6-10 membered heterocyclic ring;
RHet is optionally substituted 5-10 membered heteroaryl or optionally substituted 5-10 membered heterocyclyl;
R3 is hydroxy, —OR7 or —NR8R9;
each of R4, R5 and R6 is independently H, unsubstituted C1-C6 alkyl, or substituted C1-C6 alkyl;
R7 is unsubstituted C1-C6 alkyl, substituted C1-C6 alkyl, or a hydroxy protecting group;
each of R8 and R9 is independently H, unsubstituted or substituted C1-6 alkyl, or an amino protecting group; and
B is a natural nucleobase, a modified natural nucleobase, or an unnatural nucleobase.