Stereospecific synthesis of muscarines and allomuscarines in D- and L-series

Abstract

signals at 2.5-2.S, and (2) the absence of an AcO-1 and a H-l signal at 2 and 6, respectively. The remaining absorptions closely resembled those of 3. A careful analysis of the 400-MHz spectrum with the aid of decoupling experiments therefore established the structure 5 for this product. The elementary analysis and mass spectrum supported the structure. The mechanism for the formation of such a further reduced P sugar is, however, currently under investigation.The values of the geminal P-C-H coupling constants (e/1|P) of the presently described phosphinyl coompounds apparently depend upon the magnitude of their approximate 0=P-C-H dihedral angles illustrated in the Newman projections (Figure 1). Thus the anti conformation of the 0=P-C-H group exhibited a lower magnitude of coupling than the gauche conformation, providing a quick method for assignment of configuration of the P sugars. A similar dependence of the geminal P-C-H coupling constant of the 0=P-C-H dihedral angle has been reported for a linear and cyclic phosphonyl compound.5 The large values of the H-C-5-P geminal

Stereoselective Construction of the Tetrahydrofuran Nucleus by Alkoxyl Radical Cyclizations

“…The major product, 3,5-cis-71, was converted in two subsequent steps into (ϩ)-allo-muscarine (72). [81,82] Scheme 12 Photoreaction of pyridinethione syn-65 and BrCCl 3 , see ref. [22] Scheme 13.…”

Design, synthesis and docking studies of new furobenzopyranones and pyranobenzopyranones as photoreagent towards DNA and as antimicrobial agents

“…Some of these are used in PUVA photochemotherapy (Psoralen plus UVA) to treat a variety of skin diseases. They are also employed in extracorporeal photochemotherapy to treat cutaneous T-cell lymphomas and as selective immunosuppressive agents for the cure of various autoimmune diseases and to prevent rejection in organ transplants [1,2]. Furthermore, psoralen derivatives are now recognized as effective antiviral agents, especially against enveloped viruses such as the herpes simplex virus or HIV-1 [3,4].…”

“…The bifunctional damage, in particular the induction of ISC, was regarded as the main cause responsible for the furocoumarin toxicity, i.e., skin erythemas, genotoxicity with induction of point mutations in bacteria [1,[9][10][11][12].…”

Two Contrasting Asymmetric Approaches to Muscarine Based on 5‐endo‐trig Cyclisations

“…Examples of this idea include the first, short (but non-regioselective) approach from -glucosamic acid [12] and a subsequent synthesis by the same group starting from 2-deoxy--ribose. [13] An alternative began with 2-deoxy--ribose; [14] approaches from -mannitol, [15] isopropylidene glyceraldehyde, [16] -glucose, [17] and -mannonolactone [18] each have notable features and some the flexibility to prepare other muscarine isomers or homologues. Arguably, one of the most practical is a more recent approach from -rhamnose.…”