| 主权项 |
1. A method for preparing a compound of formula (I) the method comprising, contacting a compound of formula (II) with a boron based reducing agent, and a carbonyl compound having formula: an acylating agent, or an alkylating agent, wherein the contacting is optionally conducted in a solvent; and wherein
at each occurrence, is independently a single or double bond;L is absent, —C(O)— or —SO2—;n is 0 or 1;R1 is H, C1-C6 alkyl, C1-C6 alkoxy, OH, or —O-Pro;R2 is H, C1-C6 alkyl, C1-C6 alkoxy, OH, or —O-Pro;R3 is H, C1-C6 alkyl, C1-C6 alkoxy, OH, or —O-Pro, wherein
Pro, at each occurrence, is independently a hydroxyl protecting group;R10 is C1-C6 alkyl, C2-C6 alkenyl, C2-C6 alkynyl, C3-C8 cycloalkyl, —C1-C6 alkyl-aryl, —C2-C6 alkenyl-aryl, —C2-C6 alkynyl-aryl, —C1-C6 alkyl-heteroaryl, —C2-C6 alkenyl-heteroaryl, —C2-C6 alkynyl-heteroaryl, —C1-C6 alkyl-heterocycloalkyl, —C2-C6 alkenyl-heterocycloalkyl, —C2-C6 alkynyl-heterocycloalkyl, —C1-C6 alkyl-C3-C8 cycloalkyl, —C2-C6 alkenyl-C3-C8 cycloalkyl, —C2-C6 alkynyl-C3-C8 cycloalkyl, or C1-C6 alkoxy C1-C6 alkyl;R11 is H, absent, C1-C6 alkyl, C2-C6 alkenyl, C2-C6 alkynyl, C3-C8 cycloalkyl, —C1-C6 alkyl-aryl, —C2-C6 alkenyl-aryl, —C2-C6 alkynyl-aryl, —C1-C6 alkyl-heteroaryl, —C2-C6 alkenyl-heteroaryl, —C2-C6 alkynyl-heteroaryl, —C1-C6 alkyl-heterocycloalkyl, —C2-C6 alkenyl-heterocycloalkyl, —C2-C6 alkynyl-heterocycloalkyl, —C1-C6 alkyl-C3-C8 cycloalkyl, —C2-C6 alkenyl-C3-C8 cycloalkyl, —C2-C6 alkynyl-C3-C8 cycloalkyl, or C1-C6 alkoxy C1-C6 alkyl; wherein each aryl group is unsubstituted or substituted at one or more substitutable positions with a group that is independently C1-C6 alkyl, C2-C6 alkenyl, C2-C6 alkynyl, C1-C6 alkoxy, OPro, halo, C1-C6 haloalkyl or C1-C6 haloalkoxy; and wherein each heteroaryl group is unsubstituted or substituted at one or more substitutable positions with a group that is independently C1-C6 alkyl, C2-C6 alkenyl, C2-C6 alkynyl, C1-C6 alkoxy, OPro, halo, C1-C6 haloalkyl or C1-C6 haloalkoxy; and wherein each heterocycloalkyl group is unsubstituted or substituted at one or more substitutable positions with a group that is independently C1-C6 alkyl, C2-C6 alkenyl, C2-C6 alkynyl, C1-C6 alkoxy, OPro, halo, C1-C6 haloalkyl or C1-C6 haloalkoxy; and
R14 is H or OH;R25 is O if is a double bond, or R25 is OH, if is a single bond; provided that when the compound of formula (II) is contacted with the carbonyl compound, n is 1 and L is absent; provided that when the compound of formula (II) is contacted with the acylating agent, L is —C(O)— or —SO2—; and when the acylating agent is an acid anhydride, then n is 0; and provided that when the compound of formula (II) is contacted with the alkylating agent, L is absent. |
