137664-63-2

Upstream product

• 25581-41-3 D-erythronolactone acetonide 
• 56-86-0 L-glutamic acid 
• 134107-65-6 (3R,7aS)-3-phenyl-3,7a-dihydro-1H-pyrrolo[1,2-c]oxazol-5-one 
• 103201-79-2 (3R,7aS)-3-phenyl-tetrahydro-pyrrolo[1,2-c]oxazol-5-one 
• 152500-26-0 (S)-5-(hydroxymethyl)-1-(4-methoxyphenylmethyl)-2-pyrrolidinone 
• 138253-25-5 (S)-1-(4'-methoxybenzyl)-5-methoxymethyl-pyrrolidin-2-one 
• 138253-26-6 (S)-1-(4-Methoxy-benzyl)-5-methoxymethyl-1,5-dihydro-pyrrol-2-one 
• 138253-24-4 (S)-1-(4-Methoxy-benzyl)-5-(4-methoxy-benzyloxymethyl)-pyrrolidin-2-one 
• 254442-10-9 (3aR,6R,6aR)-5-(4-Methoxy-benzyl)-6-(4-methoxy-benzyloxymethyl)-2,2-dimethyl-tetrahydro-[1,3]dioxolo[4,5-c]pyrrol-4-one 
• 254892-77-8 (3aR,3bR,6R,8aR)-2,2-Dimethyl-6-phenyl-tetrahydro-[1,3]dioxolo[4',5':3,4]pyrrolo[1,2-c]oxazol-8-one 
• 254441-91-3 (3aR,6R,6aR)-6-Hydroxymethyl-2,2-dimethyl-tetrahydro-[1,3]dioxolo[4,5-c]pyrrol-4-one 
• 17342-08-4 (S)-Pyroglutaminol 
• 2393-23-9 4-methoxy-benzylamine 
• 137664-61-0 (3aR,6R,6aR)-6-(3,3-Dimethyl-2-oxo-butyl)-5-(4-methoxy-benzyl)-2,2-dimethyl-tetrahydro-[1,3]dioxolo[4,5-c]pyrrol-4-one 

Downstream Products

• 137664-66-5 (3aR,6R,6aR)-5-(4-Methoxy-benzoyl)-6-methoxymethyl-2,2-dimethyl-tetrahydro-[1,3]dioxolo[4,5-c]pyrrol-4-one 
• 137683-86-4 (3aR,6R,6aR)-6-Methoxymethyl-2,2-dimethyl-tetrahydro-[1,3]dioxolo[4,5-c]pyrrol-4-one 
• 137664-64-3 [(R)-1-((4R,5R)-5-{(R)-3-[4-(tert-Butyl-diphenyl-silanyloxymethyl)-oxazol-2-yl]-butylcarbamoyl}-2,2-dimethyl-[1,3]dioxolan-4-yl)-2-methoxy-ethyl]-carbamic acid tert-butyl ester 
• 138253-28-8 [(R)-1-((4R,5R)-5-Benzylcarbamoyl-2,2-dimethyl-[1,3]dioxolan-4-yl)-2-methoxy-ethyl]-carbamic acid tert-butyl ester 
• 138253-29-9 (4R,5R)-5-((R)-1-Dimethylamino-2-methoxy-ethyl)-2,2-dimethyl-[1,3]dioxolane-4-carboxylic acid benzylamide 

Relevant academic research and scientific papers

Total synthesis of (+)-calyculin A and (-)-calyculin B: Cyanotetraene construction, asymmetric synthesis of the C(26-37) oxazole, fragment assembly, and final elaboration

A convergent total synthesis leading to (+)-calyculin A and (-)-calyculin B (1 and 2), antipodes of the potent, highly selective and remarkably cell-permeable phosphatase inhibitors calyculins A and B, has been achieved. In the preceding paper we outlined the asymmetric synthesis of the C(9-25) spiroketal dipropionate subunit (+)-BC; herein we describe construction of the C(1-8) cyanotetraene, an asymmetric synthesis of the C(26-37) oxazole, fragment assembly and final elaboration to (+)-1 and (-)-2. Highlights of the synthesis include: application of a one-pot three-component Suzuki reaction for the construction of phosphonate A, a bifunctional triene precursor of the light sensitive C(1-8) cyanotetraene subunit, an asymmetric synthesis of the C(26-32) oxazole (-)-D, exploiting the Silks-Odom 77Se NMR protocol to assess enantiomeric purity, construction of the C(33-37) subtarget (-)-E in a highly stereocontrolled fashion via an acyliminium ion, and a concise, highly efficient sequence for fragment assembly and elaboration to (+)-calyculin A and (-)-calyculin B. The synthesis of (-)-2 also confirms the structure of calyculin B, previously based only on spectral comparison with calyculin A.

Stereoselective Synthesis of 2,3-Dihydroxy-4-dimethylamino-5-methoxypentanoic Acid, A Fragment of Calyculins - Determination of the Absolute Configuration of Calyculins

2,3-Dihydroxy-4-dimethylamino-5-methoxypentanoic acid (2) with (2R,3R,4R)-configuration has been stereoselectively prepared from (S)-pyroglutaminol (3) and revealed to be the enantiomer of the compound derived from calyculins (1), which provides the conclusicve evidence on the absolutr configuration of calyculins.

Calyculin synthetic studies. 2. Stereocontrolled assembly of the C(9)-C(13) dithiane and C(26)-C(37) oxazole intermediates

The C(9)-C(13) dithiane (+)-2 and C(26)-C(37) γ-amino acid/oxazole (+)-5, key building blocks for calyculin total synthesis, have been elaborated in homochiral form. Noteworthy features of the schemes include stereocontrolled generation of the C(36) steeo