2,4‐Diazabicyclo[3.3.1]nonan‐Gerüste aus
            <i>cis</i>
            ‐Benzoltrioxid

Fritsche-Lang, W.; Wilharm, P.; Hädicke, Erich; Fritz, Hans; Prinzbach, Horst

doi:10.1002/cber.19851180527

Cited by 26 publications

(11 citation statements)

References 89 publications

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“…The crystal structure of 1,3-diammonio-1,2,3-trideoxy-cis-inositol sulfate has been reported by Neis et al (2012). The importance of intramolecular hydrogen bonding in 1,3,5-trisubstituted cyclohexane derivatives has been described by Gencheva et al (2000), Saaidi et al (2008) and Neis et al (2010), and the implication of increased 1,3-diaxial repulsion on the conformation of a cyclohexane ring has been discussed by Fritsche-Lang et al (1985), Kramer et al (1998) and Kuppert et al (2006). For the synthesis, see: Merten et al (2012).…”

Section: Related Literaturementioning

confidence: 99%

Redetermination of 1,3-diammonio-1,2,3-trideoxy-cis-inositol dichloride

et al. 2012

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The crystal structure of the title compound, C6H16N2O3 2+·2Cl−, has been reported previously by Palm [Acta Cryst. (1967 ▶), 22, 209–216] from Weisenberg camera data, with R1 = 10.5%, isotropic refinement of non-H atoms and H atoms not located. We remeasured a data set of the title compound and present a more precise structure determination. The asymmetric unit contains two unique 1,3-diammonio-1,2,3-trideoxy-cis-inositol cations and four Cl− counter-ions. The cyclohexane rings of both inositol cations adopt chair conformations with two axial hydroxy groups. An extended network of hydrogen bonds is formed. The four chloride counter ions are hydrogen bonded to the hydroxy and ammonium groups of the cations by N—H⋯Cl and O—H⋯Cl interactions. The cations are aligned into wavy layers by cation⋯cation interactions of the form N—H⋯O(ax), N—H⋯O(eq) and O(ax)—H⋯O(eq). Intramolecular hydrogen bonding between the axial hydroxy groups is, however, not observed.

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Section: Related Literaturementioning

confidence: 99%

Redetermination of 1,3-diammonio-1,2,3-trideoxy-cis-inositol dichloride

et al. 2012

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“…Guanidine reacts as a nucleophile with terminal epoxides8 and cyclohexene oxides,9 but failed to react with the more hindered trans epoxide of 6 .…”

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confidence: 99%

Synthesis of (+)- and (−)-Monanchorin

Snider

2009

Org. Lett.

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The optically pure epoxy acetal was converted to the protected guanidino alcohol by reaction with NaN 3 in DMF, hydrogenation of the azide, and reaction of the amine with MeSC(NBoc)NHBoc, AgNO 3 and Et 3 N. Treatment of the protected guanidino alcohol with 9:1 CDCl 3 /TFA afforded monanchorin, whose absolute stereochemistry was assigned as shown.McKee and coworkers recently isolated the weakly cytotoxic monanchorin (1) from the sponge Monanchora ungiculata collected in the Maldive islands (see Scheme 1). 1 The carbon skeleton was assigned on the basis of 2D NMR experiments, leading to two possible aminal structures 1 and 2 that differ in the connection of the guanidine to the carbon chain. The 13 C NMR shifts fit better with calculated values for 1 suggesting that this is the correct structure. This is consistent with the known reaction of trans-2-hydroxycyclohexylguanidine with cyclohexanone to afford aminal 3, whose structure has been established crystallographically. 2 Crambesidin acid was also isolated from this sponge and other polycyclic crambescidin, ptilocaulin, and batzelladine guanidine alkaloids have been isolated from Monanchora sponges. As part of our continuing interest in the synthesis of these guanidine alkaloids, 3 we decided to investigate the synthesis of monanchorin.Monanchorin is the aminal formed from the intramolecular dehydration of erythro-4-guanidino-5-hydroxydecanal. Initially we decided to investigate the reaction of guanidine with epoxy aldehyde 4 hoping that the guanidine would add initially to the aldehyde and then to the proximal end of the epoxide to form a hemi-aminal with regiochemical control. 4 Unfortunately, treatment of 4 5 with guanidine resulted in decomposition. We then turned to the nonregioselective preparation of guanidino hydroxy acetal 5 from epoxy acetal 6.Protection of 4E-decenal (7) with HC(OMe) 3 and camphorsulfonic acid (CSA) in MeOH afforded the acetal quantitatively, which was treated with Shi's D-fructose derived ketone (8)

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“…In contrast to the large coupling of J H2,H3 (E14.0 Hz) of STs with the trans-fused streptolidine lactam moiety, 7,[12][13][14] the diagnostic coupling constant of J H2,H3 (10.8 Hz) of 1 suggested that the streptolidine lactam moiety in 1 had the cis configuration. 18,19 This was supported by NOE correlations of H-2 with H-3 and H-4 and between H-3 and H-4 in the ROESY spectrum of 1, demonstrating that these protons were on the same side of the ring system ( Figure 2b). The CD spectrum of 1 displayed a positive Cotton effect at 201 nm ascribed to the C ¼ N group in the guanidine residue 20,21 and a negative Cotton effect at 222 nm for the n-p* transition of the lactam unit, 22 which was similar to that of 3.…”

Section: Structure Elucidationmentioning

confidence: 80%