Bryostatin analogues, synthetic methods and uses

A compound having the structure represented by a formula:

• wherein:
• R3 is H′, or OH;
• R7 is absent or represents from 1 to 4 substituents on the ring to which it is attached, independently selected from:
• lower alkyl, hydroxyl, amino, alkoxyl, alkylamino, ═O, acylainino and acyloxy;
• R20 is H, OH, or -T-U—V—R′ where:
• T is —O—, —S—, —N(H)— or —N(Me)-;
• U is absent or is —C(O)—, —C(S)—, —S(O)— or —S(O)2—;
• and
• V is absent or is —O—, —S—, —N(H)— or —N(Me)-, provided that V is absent when U is absent;
• R21 is ═CR3Rb or R21 represents independent moieties R6 and Rd where:
• Ra and Rb are independently H, CO2R′, CONRaRd or R′;
• Rc and Rd are independently H, alkyl, alkenyl, alkynyl or (CH2)pCO2R′;
• R26 is H, OH or R′;
• R′ is independently selected from:
• H, C1–C10 alkyl, naphthyl, anthracyl, phenanthryl, alkenyl, alkynyl, heteroaryl, aralkyl and heteroaralkyl;
• X is —CH2—, —O—, —S— or —N(Re)— where Re is COH, CO2R′ or SO2R′, Z is —O— or —N(H)—;
• p is 1, 2 or 3;
• or a pharmaceutically acceptable salt thereof,
• excluding the compounds of Formula 1998a where R3 is H or OH and where R20 is —O—C(O)—CH3, or —O—C(O)—(CH2)6—CH3