192317-22-9

Upstream product

• 56-86-0 L-glutamic acid 
• 1338787-49-7 N-benzyl-5-O-tert-butyldimethylsilyl-4-deoxy-2,3-O-isopropylidene-D-ribono-1,4-lactam 
• 117858-84-1 N-benzyl-1,4-dideoxy-1,4-imino-2,3-O-isopropylidene-D-ribitol 
• 153172-30-6 1-amino-1,4-anhydro-N-benzyl-5-O-tertbutyldimethylsilyl-1-deoxy-2,3-O-isopropylidene-D-ribitol 
• 17342-08-4 (S)-Pyroglutaminol 
• 74936-93-9 (S)-5-oxopyrrolidine-2-carbonyl chloride 
• 100-52-7 benzaldehyde 
• 103201-79-2 (3R,7aS)-3-phenyl-tetrahydro-pyrrolo[1,2-c]oxazol-5-one 
• 134107-65-6 (3R,7aS)-3-phenyl-3,7a-dihydro-1H-pyrrolo[1,2-c]oxazol-5-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 

Downstream Products

• 1338787-20-4 N-benzyl-4-deoxy-2,3-O-isopropylidene-5-O-methanesulfonyl-D-ribono-1,4-lactam 
• 1338787-22-6 S-(N-benzyl-4,5-dideoxy-2,3-O-isopropylidene-D-ribono-1,4-lactam-5-yl)-N-(tert-butoxycarbonyl)-1-homocysteine tert-butyl ester 
• 1338787-23-7 S-(N-benzyl-4,5-dideoxy-D-ribono-1,4-lactam-5-yl)-1-homocysteine 

Relevant academic research and scientific papers

Inhibition of LuxS by S-ribosylhomocysteine analogues containing a [4-aza]ribose ring

LuxS (S-ribosylhomocysteinase) catalyzes the cleavage of the thioether linkage of S-ribosylhomocysteine (SRH) to produce homocysteine and 4,5-dihydroxy-2,3-pentanedione (DPD), the precursor to a small signaling molecule that mediates interspecies bacteria

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.

Sugar lactams and lactim ethers, useful precursors of cyclic amidines, from intramolecular nucleophilic displacements

The cyclisation of the conjugate base of N-aryl-2,3:5,6-di-O-isopropylidene-4-O-methanesulfonyl-D- gulonamides gave the D-allonolactam acetals. Sodium methoxide-promoted cyclisation of 2,3:5,6-di-O-isopropylidene-4-O-methanesulfonyl-D-mannononitrile gave the D-talonolactim ether. Tetrazole formation without isolation of the intermediate azide was illustrated by the conversion of the aforementioned nitrile sulfonate into the D-talonotetrazole. Cyclic amidines were prepared from the lactam and lactim ether derivatives. The D-allono derivatives were also converted into D-ribono-1,4 lactam and amidine derivatives.