The reaction rate of a catalyzed reaction is faster than the reaction rate of the uncatalyzed reaction at the same temperature.2081-44-9, Name is Tetrahydro-2H-pyran-4-ol, molecular formula is C5H10O2. In a Patent，once mentioned of 2081-44-9, Recommanded Product: 2081-44-9
4-HYDROXYQUINOLINE-3-CARBOXAMIDES AND HYDRAZIDES AS ANTIVIRAL AGENTS
From EXEMP_CLAIMS : 1. A compound of formula I or pharmaceutically acceptable salts thereof wherein A is: a) -CH2-, or b) -NH-; R1, R2, R3 and R4 are independently a) -H, b) halo, c) -CN, d) -NO2, e) aryl, f) het, g) -OR5, h) C1-12 alkyl, i) C1-12 alkyl substituted with one to three -CN, halo, -NO2, OR5, -C(=O)R5, -COOR5, het, aryl, -SR5, -OR6, -NR7R8, -OP(=O)(R9)2, -OPH(=O)R9, -OC(=O)R10, -O-glycyl, -O-valyl or -O-lysyl, j) -C?CR11, k) -CH=CH-R12, l) -(CH2)m-C(=O)R13, m) -SR14, n) -C(=S)R15, o) -(CH2)m-SOiR13, p) -NR7R8, q) -NHSOiR13, r) R1 and R2 taken together are het or C4-6 cycloalkyl, or s) R2 and R3 taken together are het or C4-6 cycloalkyl; R5 is a) H, b) C1-8 alkyl, optionally substituted with one to three -OH, CN, C1-4 alkoxy, halo, -NO2, het or aryl, c) aryl, or d) het; R6 is a) -SO2C1-6 alkyl, b) -SO2-(CH2)m-aryl, or c) -SO2-(CH2)m-het; R7 and R8 are independently a) H, b) C1-8 alkyl, optionally substituted with one to three -NO2, halo, -CN, OR5, aryl, het, C3-6 cycloalkyl, C1-6 alkynyl, C1-6 alkenyl, -SR14, or -NR16R17, c) aryl, d) het, e) -(CH2)m-C(=O)OR5, f) -(CH2)m-C(=O)R5, or g) R7 and R8 taken together to form het; R9 is a) -OH, or b) -OC1-8 alkyl; R10 is a) H, b) C1-8 alkyl, c) -NR7R8, c) C1-8 alkyl substituted with one to two halo, het, -NR7R8, -COOH -O(CH2)mCOOH or -C(=O)N(C1-4 alkyl)(CH2)nS(=O)2O-M+; R11 is a) C1-8 alkyl, b) C1-8 alkyl substituted with one to three -CN, halo, -NO2, -COOR5, -C(=O)R5, -SR5, aryl, -OR5, -NR7R8, -OP(=O)(R9)2, -OPH(=O)R9 -OC(=O)R10, -O-glycyl, -O-valyl or -O-lysyl or c) -(CH2)m-het; R12 is a) H, b) -CN, c) C1-8 alkyl, d) C1-8 alkyl substituted with one to three -CN, halo, -NO2, -C(=O)R5, -COOR5, aryl, het, -SR5, -OR5, -NR7R8, -OP(=O)(R9)2 or -OPH(=O)R9, e) -C(=O)R5, or f) -COOR5; R13 is a) C1-8 alkyl, b) C1-8 alkyl substituted one to three -CN, halo, -NO2, -C(=O)R5, het, aryl, -COOR5, -SR5, -OR5 or -NR7R8, c) het, d) aryl, e) -NR7R8, f) OR5, h) halo; R14 is a) C1-8 alkyl, or b) C1-8 alkyl substituted with one to three -CN, halo, -NO2, -C(=O)R5, -COOR5, het, aryl, -OR5, or -NR7R8; R15 is a) -NH2, or b) -NHNH2; R16 and R17 is independently a) H, b) C1-4 alkyl, b) -C(=O)C1-4 alkyl, or c) -C(=O)-(CH)m-aryl; aryl is phenyl or naphthyl, optionally substituted with R18; het is a 5-, 6- or 7-membered saturated or unsaturated heterocyclic ring having 1-3 heteroatoms selected from the group consisting of nitrogen, oxygen and sulfur, wherein the heteroclyclic ring is optionally fused to a benzene ring, wherein aryl, het and benzene ring are optionally substituted with R18; R18 is a) halo, b) -NO2, c) phenyl, optionally substituted with one to five -OH, -CN, halo, -NO2, C1-6 alkyl, het, or OC1-4 alkyl, d) C1-8 alkyl, optionally substituted with one to three halo, -CN, -NO2, aryl, -SR5, -OR5 or -NR7R8, e) OR5, or f) -SO2NH2; M is sodium, potassium or lithium atom; i is 1 or 2; m is 0, 1, 2, or 4; n is 1, 2, 3 or 4; and with the following provisos: (a) where R2, R3 and R4 are each hydrogen, then R1 is other than methoxy, (b) where R4 is Cl, and R2 and R3 are each hydrogen, then R1 is other than methyl, (c) where R1 is hydrogen, R2 and R4 are each fluoro, R3 is het, then het is other than substituted piperazinyl, (d) where R1 and R3 are each hydrogen, R2 is fluoro, then R4 is other than fluoro, (e) where R2 and R4 are each hydrogen, R1 is fluoro, then R3 is other than fluoro, (f) where R1 and R3 are each hydrogen, R2 is chloro, then R4 is other than chloro, (g) where R1, R2 and R3 are each hydrogen, then R4 is not bromo, (h) where R1, R3 and R4 are each hydrogen, then R2 is not trifluoromethoxy, (i) where R1, R2 and R4 are each hydrogen, then R3 is not trifluoromethoxy, and (j) where R1, R2 and R3 are each hydrogen, then R4 is not morpholinyl.
The reactant in an enzyme-catalyzed reaction is called a substrate. Enzyme inhibitors cause a decrease in the reaction rate of an enzyme-catalyzed reaction.I hope my blog about 2081-44-9 is helpful to your research., Recommanded Product: 2081-44-9
Reference：
Tetrahydropyran – Wikipedia,
Tetrahydropyran – an overview | ScienceDirect Topics