WO2012164476A1 - New tricyclic compounds, process for their manufacture and their use as ligands of the beta amyloid peptides - Google Patents

Abstract

The synthesis and the use of the compounds with glycofused tricyclic structure as ligands of the Αβ peptides is the object of the invention. Such compounds result to be chemically stable, they have a high solubility under physiological conditions and they are suitable for functionalizations which make them easily conjugable to other entities to allow a therapeutic and diagnostic use thereof. The capability of the compounds to link the Αβ peptide, in the various shapes thereof, and in particular the most toxic one, represented by the oligomers, was evaluated through NMR experiments.(III).

Description

NEW TRICYCLIC COMPOUNDS, PROCESS FOR THEIR MANUFACTURE AND THEIR USE AS LIGANDS OF THE BETA AMYLOID PEPTIDES

DESCRIPTION

The present invention relates to new glycofused tricyclic compounds, a process for their manufacture and their use as ligands of the β amyloid peptides (Αβ).

State of art

Several compounds have demonstrated to be able to inhibit the aggregation of Αβ peptides. Among them there are small molecules bearing aromatic entities which have shown to have inhibitory activities characterized by IC₅₀ comprised between 100 nM and 100 μΜ¹. Among these molecules there are several natural compounds such as curcumin^2,3, the polyphenols existing in wine¹, apomorphine⁴, porphyrins⁵'⁶, fatty acids omega-3⁷, the tannic acid¹'⁸, vitamin A and β-carotene⁹, rifampicin and rifamicin B⁵, tetracycline⁸'¹⁰, coenzyme Qio¹¹ , apart from several anti-inflammatory¹²'¹³ and anti— Parkinson¹⁴'¹⁵ agents.

By way of example, the work "Beta Amyloid Aggregation Inhibitors: Small Molecules as Candidate Drugs for Therapy of Alzheimer Disease" Francesca Re, Cristina Airoldi, Cristiano Zona, Massimo Masserini, Barbara La Ferla, Nicoletta Quattrocchi, Francesco Nicotra^*, Curr. Med Chem., 2010, 17, 2990-3006; summarizes the main compounds with low molecular weight identified up to now as inhibitors of the aggregation of Αβ peptides.

Although the compounds able to inhibit the aggregation of Αβ peptides are numerous, it is not still clear how they act; moreover, many of these molecules have problems associated to the poor stability and solubility thereof, or to the fact that some thereof have already well known pharmacological activities related to the treatment of pathologies different from Alzheimer's disease, preventing to evaluate correctly the real therapeutic effect thereof with respect to the latter. From this the need is felt for developing compounds able to interact with the Αβ peptides and which, at the same time, do not have the above-mentioned limitations and therefore they can reveal to be useful both therapeutic and diagnostic instruments against Alzheimer's disease and all pathological events associated to the aggregation of these peptides.

The work "Sc(OTf)₃-catalyzed synthesis of pyrano[3,2-b]-1-benzopyrans from D- glycals" J. S. Yadav, B. V. S. Reddy, L. Chandraiah, B. Jagannadh, S. Kiran Kumar and Ajit C. Kunwar Tetrahedron Letters, 2002, 43, 4527-4530 describes a general process of synthesis of pyrano[3,2-b]-1-benzopyrans similar to the compounds of the present invention, however without specifying any use thereof.

Now it has been found that particular glycofused tricyclic compounds, apart from having the substantial capability of interacting with the Αβ peptides, demonstrated through molecular recognition studies carried out by means of spectroscopy of Nuclear Magnetic Resonance (NMR), have a high chemical stability and a remarkable solubility in water. These features make such compounds easily useable both with diagnostic and therapeutic purpose. Furthermore, the hydrophilicity/hydrophobicity properties of such compounds can be easily modulated by introducing suitable substituents onto the oxydrilic groups, so as to meet specific needs such as the administration and the passage of the ematoencephalic barrier. The presence of the glycofused saccharidic mojety allows then an easy functionalization of the compounds, so as to make them able to be conjugated to other entities (particles, polymeric supports, etc.). Such feature results extremely useful both in the therapeutic and diagnostic field. This conjunction, in fact, allows to implement molecular devices which can be optimized for different purposes:

selective delivery of ligands/inhibitors of amyloid peptides (for example conjunction with agents allowing to cross the ematoencephalic barrier);

- generation of multivalent devices (having multiple copies of the same ligand or different ligands) in order to increase the therapeutic/diagnostic efficiency of the same;

generation of devices allowing, based upon the different chemical-physical features thereof, to modulate the pharmacokinetic properties of anti-Alzheimer agents.

Furthermore, the compounds of the invention can be conjugated to other interest entities, for example fluorophore groups, by obtaining compounds which can be used for diagnostic purposes to reveal for example through fluorescence, the presence of Αβ peptides, both ex vivo and in vivo.

Therefore, the object of the present invention are the compounds according to claim 1 and the following ones, the use thereof as ligands of the β amyloid peptides (Αβ) and pharmaceutically compositions containing such compounds.

The compounds of claim 1 are represented by the formula III

I I I

wherein R1 , R2, R4, and R5 can be equal or different and they can be H , alkyl groups (C1 -C5), OH , OAIkyl, N H₂ ;

R3, R6 can be equal or different and they can be H , alkyl groups (C1 -C5)

- X can be -0-, -OH-, -N H₂-, -NHCO-, -S- - Z can be -(CH₂)n-, -(CH₂CH₂0)n- with (1 <n<5) or absent

- Y can be R3, H , OH, N H₂, N₃, SH, COOH or a fluorophore group, an agent for the passage of the ematoencephalic barrier, a multivalent device.

with exclusion of the following compounds

An object of the present invention is also the process of claim 1 1.

The present invention relates to glycofused tricyclic structures such as ligands of Αβ peptides. The synthesis of some precursors was already published (Tetrahedron Letters, 43, 2002, 4527-4530). However, in such publication no mention is made to the use of these molecules in the fields relating the present invention. The inventors have synthetized a small library of the compounds (3-22) wherein different substituents on the aromatic ring were introduced, and the saccharidic entity has been modified, so as to evaluate the influence of both portions of the tricyclic structure, as well as the stereochemistry of the ring deriving from sugar, in the interaction with the peptides. In particular, the saccharidic unit derives, in the compounds 1 -9 and 1 3-19, from monosaccharide D-galactose, in the compounds 10-12 e 20-22, from monosaccharide D-glucose.

The synthesis of the derivatives provides the reaction of D-glycals protected with O- hydroxybenzaldehydes variously substituted on the aromatic ring, in presence of trimethylorthoformate and Sc(OTf)₃, the latter as catalyzer. The reaction is performed in dichloromethane at room temperature, with yields comprised between 21 and 91 %. Differently from what already described in literature, in some cases the formation of diastereoisomeric mixtures at the substituent OMe in position C7, with variable diastereoisomeric ratios, can be noted.

The interaction studies with the Αβ1-42 amyloid peptide were performed on the deprotected products 13-22 and on the fluorescent derivative 26. The obtained compounds were tested in order to verify the capability thereof to link the Αβ1-42 peptide through peptide-ligand interaction studies carried out by means of NMR spectroscopy. In particular experiments of Saturation Transfer Difference (STD) and of transferred-NOESY (tr-NOESY).¹⁶'¹⁷'¹⁸ were performed.

Such experiments allowed not only to check the capability of the compounds according to the invention to act as ligands of the Αβ peptides, but also to define a ranking of affinities of the same, as well as to identify the bind epitope of the molecules, that is the structural portions of the same directly involved in the interaction with the peptide. Studies of mechanics (molecular mechanics, MM) and molecular dynamics (molecular dynamics, MD), at last, integrated the NMR data by allowing to implement a small study of structure-activity correlation (Structure-Activity Relationship, SAR), in order to confirm definively the structural requirements necessary to the recognition and to the link of the biological target.

Synthesis of the compounds

General considerations: all anhydrous solvents are anhydrified on molecular sieves at least 24 h before use. The chromatographies on thin layer (TLC) are performed on silica gel plates 60 F254 (Merck), detected at the UV lamp when possible and developed with a solution of H₂S0₄/EtOI-l/l-l₂0 (5:45:45) or a solution of (NH₄)₆Mo₇024 (21 g), Ce(S0₄)₂ (1 g), H₂S0₄ cone. (31 mL) in water (500 mL) and heated at 150°C. Flash chromatographies are performed with silica gel 230-400 mesh (Merck). Spectra ¹H and ¹³C NMR are recorded at 25°C, if not otherwise mentioned, with an instrument Varian Mercury 400 MHz. The identification of chemical shift, reported in ppm, is referred to the peaks of the corresponding solvent. HRMS are performed on an instrument QSTAR elite LC/MS/MS with a nanospray ionic source, whereas MS are performed with a system ESI QTRAP 2000 LC/MS/MS. The measurements of optical rotation are performed on a polarimeter Atago Polax-2L and they are reported in units of 10^"1 deg-cm²-g^"1.

General synthetic procedure for the synthesis of the protected products 3-12: page 4530, reference 9 of publication "Tetrahedron Letters, 43, 2002, 4527-4530" (figure 1 ) A mixture containing suitable O-hydroxybenzaldehyde (2.5 eq.), trimethylorthoformate (2.5 eq.) and scandium triflate (3%mol) in CH₂CI₂, is kept under stirring at room temperature for 20 min. Then, it is cooled at 0°C and tri-O-benzyl glycal (1 eq.) is slowly added. The so-obtained reaction mixture is left under stirring at room temperature for 30 min. At the end of reaction, checked by TLC, the reaction mixture is diluted with CH₂CI₂, washed with water, anhydrified on anhydrous sodium sulfate, filtered and the solvent is evaporated at reduced pressure. The raw residue is purified by means of flash chromatography. General synthetic procedure for the deprotection of the protected products 3-12 to give the products 13-22. (figure 2).

To a solution 6 mM of protected compound in previously degassed AcOEt/MeOH 1 :1 , Pd(OH)₂ 5% mol is added and the reaction is put under atmosphere of H₂. At the end of the reaction, checked by TLC, the catalyst is eliminated by filtration and the solvent is evaporated under reduced pressure. The raw residue is purified by means of flash chromatography.

Synthetic procedure for the synthesis of the product 23.

To a solution of compound 22 (1 .63mmol / 482 mg) in anydrous pyridine (3.2 mL), cooled at 0°C and kept under stirring, a solution of p-toluensulfonylchloride (574mg/3 mmol), in anydrous pyridine too (3.75 mL) is added dropwise. The reaction mixture is left under stirring at room temperature for one night. At the end of the reaction, checked by TLC (eluent: CHCI₃/MeOH 9.5:0.5), the solvent is evaporated at reduced pressure and the raw residue is purified by flash chromatography (eluent: EP/AcOEt 5:5). The compound 23 under the form of white solid with the 95% yield is obtained. Synthetic procedure for the synthesis of the product 24.

To a solution of compound 23 (1.55mmol / 700mg) in anydrous DMF (4mL), a solution of NaN₃ (4.65mmol/302mg) in anydrous DMF too (4mL) is added. The reaction mixture is left under stirring a 100°C for 12 h. At the end of the reaction, checked by TLC (eluent: EP/AcOEt 5:5), it is left to cool down, it is filtered to eliminate the colourless precipitate and the solvent is evaporated. The raw residue is purified by flash chromatography (EP/AcOEt 6:4). The compound 24 under the form of white solid with the 60% yield is obtained.

Synthetic procedure for the synthesis of product 25.

To a solution 6 mM of compound 24 in previously degassed MeOH, Pd Lyndlar 5% mol is added and the reaction is put under H₂ atmosphere. At the end of the reaction, checked by TLC, the catalyst is eliminated by filtration and the solvent is evaporated at reduced pressure. The raw residue is used in the subsequent reaction.

The shown process relates to the insertion of a specific fluorophore, but it can be considered a way of example for other fluorophores/compounds.

Synthetic procedure for the synthesis of the product 26. (Figure 2A

7-hydroxycumarine-4-acetic acid (24.6mg / 0-1 12mmol) and I'HBTU (O-benzotriazole- N,N,N',N'-tetramethyl-uronium-hexafluor-phosphate)(53.1 mg/0.14mmol) are dissolved in anydrous DMF (1.3 mL). To the reaction mixture, at room temperature diisopropylethylamine (DIPEA) (0.28mmol / 48uL) is added. It is cooled at 0°C and dicyclohexylcarbodiimide (DIC) (0.14mmol / 22uL) is added, followed by the compound 25 (0.093mmol), dissolved in anydrous DMF too. The reaction mixture is left under stirring at room temperature for 12h. At the end of the reaction, checked by TLC (eluent: AcOEt/MeOH/H₂0 8:2:0.5), the solvent is evaporated and the raw residue is purified by flash chromatography (eluent: CHCI₃/MeOH 9.5:0.5) by obtaining the compound 26 under the form of green solid with a 43% yield (two passages).

By following the scheme of figure 2A, as reported previously, the compounds of formula 1 can be produced.

wherein

Η,Η,Η,ΟΗ;

Ri . ,^2,^3,^4⁼ NH₂ Η,Η,ΟΗ

Ri . ,^2,^3,^4⁼ ΟΗ,Η,Η,ΟΗ

Ri ! ,F¾ ,R3,R₄ ⁼ ΟΜΘ,Η,Η,ΟΗ

Ri . ,^2,^3,^4⁼ CH₃ H,H,OH

Ri 1 ,^R2,^R3,^R4⁼ H, ΟΜΘ,Η,ΟΗ

Ri 1 ,^R2,^R3,^R4⁼ H,CH₃ H,OH

Ri . ,^R2,^R3,^R4⁼ CH₃ H,OH,H

Ri 1 ,^R2,^R3,^R4⁼ H, ΟΜΘ,ΟΗ,Η

Ri , ,^R2,^R3,^R4⁼ H,CH₃ OH,H

and Y represents a group chosen from the class formed by fluorophores, agents for the passage of the ematoencephalic barrier, multivalent devices.

Using the described synthetic procedures, and by referring to figures 1 and 2, the herebelow reported compounds were synthetized.

Protected compounds 3-12

(2R,3R,4R, 4aS,5R/S,10aR)-3,4-bis(benzyloxy)-2-(benzyloxymethyl)-5-methoxy- 2,3,4,4a,5,10a-hexa hydropyran[2,3-b]chromene (compound 03): yield: 59%, C5 R/S 92/8

(5R)

¹H.NMR (400 MHz, CDCI₃) δ 7.55 (d, J = 7.6 Hz, 1 H, H6), 7.37 - 7.22 (m, 15H, Ar), 7.23 - 7.15 (m, 1 H, H8), 6.99 (t, J = 7.5 Hz, 1 H, H7), 6.83 (d, J = 8.1 Hz, 1 H, H9), 5.66 (d, J = 2.9 Hz, 1H, MOa), 4.96 (d, J = 11.4 Hz, 1H, OCH₂Ph), 4.77 (d, J = 4.3 Hz, 1H, H5), 4.62 - 4.31 (m, 5H, OCH₂Ph), 4.18 (t, J = 6.4 Hz, 1H, H2), 3.79 (s, 1H, H3), 3.68 - 3.63 (m, 1 H, H4), 3.63 - 3.59 (m, 2H, CH₂0), 3.58 (s, 3H, OMe), 3.36 - 3.26 (m, 1 H, H4a); ¹³C NMR (101 MHz, CDCI₃) δ 152.27, 139.03, 138.89, 138.15, 129.12, 128.62, 128.44, 128.41, 128.38, 128.13, 128.01, 127.95, 127.77, 127.55, 126.26, 122.43, 121.38, 115.59, 97.74, 76.22, 75.62, 75.16, 73.97, 73.71, 72.78, 71.71, 69.13, 57.10, 34.72. [a]_D ²⁰= +5,3 (c=1, CHCI₃). MS: m/z calculated [M + Na]⁺ = 575.2, [M + K]⁺ = 591.2; measured [M + Na]⁺= 575.3, [M + K]⁺= 591.3. (5S)

¹H NMR (400 MHz, CDCI₃) δ 7.39 - 7.24 (m, 13H, Ar), 7.24 - 7.20 (m, 1H, H6), 7.18 (dd, J = 7.0, 2.2 Hz, 2H, Ar), 7.07 (d, J = 7.4 Hz, 1H, H8), 6.88 (m, 2H, H7, H9), 5.71 (d, J = 3.2 Hz, 1H, MOa), 4.92 (d, J = 11.5 Hz, 1H, OCH₂Ph), 4.54 (ddd, J = 34.5, 23.4, 11.7 Hz, 5H, OCH₂Ph), 4.40 (d, J = 2.1 Hz, 1H, H5), 4.20 (M, 1H, H2), 3.98 (s, 1 H, H3), 3.72 - 3.64 (m, 2H, CH₂0), 3.37 (s, 3H, OMe), 3.32 (dd, J = 11.8, 2.4 Hz, 1 H, H4), 3.06 -2.98 (m, 1H, H4a).¹³C NMR (101 MHz, CDCI₃) δ 153.89, 138.79, 138.09, 137.76, 131.20, 130.35, 128.67, 128.64, 128.50, 128.25, 128.21, 128.03, 128.01, 127.85, 127.83, 120.81, 118.54, 116.96, 95.00 , 75.17, 74.79 , 74.77, 73.79, 71.62, 71.53, 71.52, 68.94, 56.38, 37.70, 29.93. [a]_D ²⁰= +8,7 (c=1, CHCI₃). MS: m/z calculated [M + Na]⁺= 575.2, [M + K]⁺= 591.2; measured [M + Na]⁺= 575.3, [M + K]⁺= 591.3. (2R,3R,4R, 4aR,5R,10aR)-3,4-bis(benzyloxy)-2-(benzyloxymethyl)-5-methoxy-7- nitro-2,3,4,4a,5,10a-hexahydropyran[2,3-b]chromene (compound 04): yield: 40%, C5R/S 100/0

¹H NMR (400 MHz, CDCI₃) δ 8.44 - 8.41 (m, 1H, H6), 8.08 (dd, J = 9.0, 2.8 Hz, 1H, H8), 7.43 - 7.17 (m, 15H, Ar), 6.87 (d, J = 9.0 Hz, 1H, H9), 5.73 (d, J = 2.9 Hz, 1H, MOa), 4.96 (d, J = 11.3 Hz, 1H, OCH₂Ph), 4.73 (t, J = 7.4 Hz, 1H, H5), 4.64-4.36 (m, 5H, OCH₂Ph), 4.11 (t, J = 6.4 Hz, 1H, H2), 3.86 (s, 1H, H3), 3.64 (dd, J = 9.2, 5.8 Hz, 2H, CH₂0), 3.59 (d, J = 7.4 Hz, 3H, OMe), 3.50 (dd, J = 1 1.1 , 2.5 Hz, 1 H, H4), 3.41 - 3.32 (m, 1 H, H4a). ¹³C NMR (101 MHz, CDCI₃) δ 157.58, 142.33, 138.72, 138.01 , 137.95, 128.68, 128.53, 128.42, 128.39, 128.23, 128.18, 128.08, 127.94, 127.81 , 125.33, 123.31 , 123.21 , 1 16.20, 98.87, 75.28, 75.23, 74.68, 73.83, 73.02, 72.39, 72.13, 68.95, 57.10, 33.96. [a]_D ²⁰= -4,5 (c=1 , CHCI₃). MS: m/z calculated [M + H]⁺ = 598.2, [M + Na]⁺ = 620.2, [M + K]⁺ = 636.2; measured [M + H]⁺ = 598.3, [M + Na]⁺ = 620.4, [M + K]⁺ = 636.4.

(2R,3R,4R, 4aR,5R,10aR)-3,4,7-tris(benzyloxy)-2-(benzyloxymethyl)-5-methoxy- 2,3,4,4a,5,10a-hexahydropyran[2,3-b]chromene (compound 05): yield: 35%, C5

R/S 100/0

¹H NMR (400 MHz, CDCI₃) δ 7.52 - 7.25 (m, 20H, Ar), 7.23 (d, J = 2.2 Hz, 1 H, H6), 6.86 (dd, J = 8.8, 3.0 Hz, 1 H, H8), 6.81 - 6.74 (m, 1 H, H9), 5.64 (d, J = 2.9 Hz, 1 H, H10a), 5.10 - 4.95 (m, 3H, OCH₂Ph), 4.76 (d, J = 4.4 Hz, 1 H, H5), 4.64-4.34 (m, 5H, OCH₂Ph), 4.20 (t, J = 6.5 Hz, 1 H, H2), 3.83 (s, 1 H, H3), 3.67 (dd, J = 1 1 .1 , 2.6 Hz, 1 H, H4), 3.65 - 3.61 (m, 2H, CH₂0), 3.58 (s, 3H, OMe), 3.36 - 3.25 (m, 1 H, H4a). ¹³C NMR (101 MHz, CDCIs) δ 149.98, 139.05, 138.93, 138.16, 130.59, 129.64, 128.61 , 128.43, 128.40, 128.36, 128.13, 127.97, 127.94, 127.75, 127.52, 126.52, 121 .97, 1 15.37, 97.62, 76.33, 75.66, 75.16, 73.93, 73.71 , 72.69, 71.65, 69.15, 57.1 1 , 34.78, 20.99. [a]_D ²⁰= -5,5 (c=1 , CHCI₃); MS: m/z calculated [M + Na]⁺ = 681.3, [M + K]⁺ = 697.3; measured [M + Na]⁺ = 681 .5, [M + K]⁺ = 697.4.

(2R,3R,4R, 4aR,5R/S,10aR)-3,4-bis(benzyloxy)-2-(benzyloxymethyl)-5,7- dimethoxy-2,3,4,4a,5,10a-hexahydropyran[2,3-b]chromene (compound 06): yield: 73%, C5 R/S 85/15

(5R)

¹H NMR (400 MHz, CDCI₃) δ 7.37 - 7.21 (m, 15H, Ar), 7.11 (d, J = 0.9 Hz, 1H, H6), 6.76 (d, 2H,H8 and H9), 5.61 (d, J = 2.9 Hz, 1H, MOa), 4.96 (d, J = 11.4 Hz, 1H, OCH₂Ph), 4.74 (d, J = 4.4 Hz, 1H, H5), 4.60-4.36 (m, 5H, OCH₂Ph), 4.18 (t, J = 6.4 Hz, 1H, H2), 3.80 (s, 4H, ArOMe and H3), 3.66 (dd, J = 11.1, 2.6 Hz, 1H, H4), 3.61 (dt, J = 7.0, 3.4 Hz, 2H, CH₂0), 3.57 (s, 3H, OMe), 3.33 - 3.24 (m, 1H, H4a).¹³C NMR (101 MHz, CDCI₃) δ 154.39, 146.10, 139.05, 138.92, 138.16, 128.62, 128.44, 128.41, 128.38, 128.14, 127.97, 127.95, 127.76, 127.54, 123.12, 116.33, 115.18, 110.81, 97.61, 76.27, 75.76, 75.16, 73.92, 73.72, 72.77, 71.65, 69.14, 57.07, 56.06, 34.72. [a]_D ²⁰= +7,1 (c=1, CHCI₃); MS: m/z calculated [M + K]⁺ = 621.2; measured [M + K]⁺ = 621.5.

(5S)

¹H NMR (400 MHz, CDCI₃) δ 7.39 - 7.15 (m, 15H, Ar), 6.84 - 6.76 (m, 2H, H8 and H9), 6.58 (s, 1H, H6), 5.64 (d, J = 3.1 Hz, 1H, MOa), 4.91 (d, J = 11.5 Hz, 1H, OCH₂Ph), 4.66 - 4.40 (m, 5H, OCH₂Ph), 4.35 (d, J = 2.0 Hz, 1H, H5), 4.26 - 4.17 (m, 1H, H2), 4.00 (s, 1H, H3), 3.76 (s, 3H, ArOMe), 3.70 - 3.63 (m, 2H, CH₂0), 3.40 (s, 3H, OMe), 3.34 (dd, J = 11.8, 2.3 Hz, 1H, H4), 3.03 - 2.94 (m, 1H, H4a).¹³C NMR (101 MHz, CDCI₃) δ 153.63, 147.66, 138.79, 138.10, 137.74, 128.63, 128.50, 128.46, 128.42, 128.25, 128.21, 128.03, 128.03, 127.97, 127.89, 127.83, 127.72, 127.50, 119.01, 117.67, 116.63, 115.27, 99.18, 94.88, 74.97, 74.80, 73.79, 71.60, 71.49, 71.42, 70.65, 70.02, 69.88, 68.96, 56.57, 55.96, 37.60. [a]_D ²⁰= +6,6 (c=1, CHCI₃); MS: m/z calculated [M + K]⁺ = 621.2; measured [M + K]⁺ = 621.6. (2R,3R,4R, 4aR,5R/S,10aR)-3,4-bis(benzyloxy)-2-(benzyloxymethyl)- 7-methyl-5- methoxy-2,3,4,4a,5,10a-hexahydropyran[2,3-b]chromene (compound 07): yield 91%, C5 R/S 95/5

¹H NMR (400 MHz, CDCI₃) δ 7.33 (d, J = 7.1 Hz, 1H, H6), 7.31 - 7.21 (m, 15H, Ar), 6.99 (d, J = 7.3 Hz, 1H, H8), 6.72 (d, J = 8.2 Hz, 1H, H9), 5.61 (d, J = 2.9 Hz, 1H, MOa), 4.96 (d, J = 11.4 Hz, 1H, OCH₂Ph), 4.74 (d, J = 4.5 Hz, 1H, H5), 4.62 - 4.33 (m, 5H, OCH₂Ph), 4.18 (t, J = 6.4 Hz, 1H, H2), 3.80 (s, 1H, H3), 3.66 (dd, J = 11.2, 2.6 Hz, 1H, H4), 3.61 (dd, J = 6.3, 4.1 Hz, 2H, CH₂0), 3.57 (s, 3H,0Me), 3.33 - 3.23 (m, 1H, H4a), 2.31 (s, 3H, Me).¹³C NMR (101 MHz, CDCI₃) δ 149.98, 139.05, 138.93, 138.16, 130.59, 129.64, 128.61, 128.43, 128.40, 128.36, 128.13, 127.97, 127.75, 127.52, 126.52, 121.97, 115.37, 97.63, 76.92, 76.33, 75.66, 75.16, 73.93, 73.71, 72.69, 71.65, 69.15, 57.1, 34.78, 20.99. [a]_D ²⁰= -5,2 (c=1, CHCI₃); MS: m/z calculated [M + H]⁺ = 567.3, [M + Na]⁺ = 589.3, [M + K]⁺ = 605.2; measured [M + H]⁺ = 567.6, [M + Na]⁺= 589.5, [M + K]⁺= 605.6.

(5S)

¹H NMR (400 MHz, CDCI₃) δ 7.40 - 7.13 (m, 15H, Ar), 7.01 (dd, J = 8.3, 1.7 Hz, 1H, H8), 6.82 (s, 1H, H6), 6.75 (d, J = 8.3 Hz, 1H, H9), 5.66 (d, J = 3.2 Hz, 1H, MOa), 4.92 (d, J = 11.5 Hz, 1 H, OCH₂P ), 4.65 - 4.42 (m, 5H, OCH₂Ph), 4.37 - 4.30 (d, J = 2.0 Hz 1H, H5), 4.26-4.17 (m, 1H, H2), 3.98 (s, 1H, H3), 3.72 - 3.63 (m, 2H, CH₂0), 3.38 (s, 3H, ArOMe), 3.36 - 3.29 (dd, J = 2.38, 11.78 Hz, 1H, H4), 3.06 - 2.93 (m, 1H, H4a), 2.26 (s, 3H, Me).¹³C NMR (101 MHz, CDCI₃) δ 151.53, 138.81, 138.10, 137.77, 131.35, 131.03, 129.91, 128.64, 128.60, 128.54, 128.49, 128.26, 128.21, 128.01, 127.93, 127.82, 118.18, 116.64, 94.89, 75.00, 74.84, 74.80, 73.79, 71.55, 71.47, 71.35, 68.96, 56.42, 37.60, 29.93, 20.77. [a]_D ²⁰= -2,1 (c=1, CHCI₃); MS: m/z calculated [M + H]⁺ = 567.3, [M + Na]⁺ = 589.3, [M + K]⁺ = 605.2; measured [M + H]⁺ = 567.6, [M + Na]⁺= 589.5, [M + K]⁺= 605.6.

(2R,3R,4R, 4aR,5R/S,10aR)-3,4-bis(benzyloxy)-2-(benzyloxymethyl)-5,8- dimethoxy-2,3,4,4a,5,10a-hexahydropyran[2,3-b]chromene (compound 08): yield 64%, C7 R/S 53/47

(5R)

¹H NMR (400 MHz, CDCI₃) δ 7.42 (d, J = 8.6 Hz, 1H, H6), 7.37 - 7.21 (m, 15H, Ar),6.56 (dd, J = 8.5, 2.4 Hz, 1H, H7), 6.39 (d, J = 2.4 Hz, 1H, H8), 5.62 (d, J = 2.8 Hz, 1H, MOa), 4.96 (d, J = 11.4 Hz, 1H, OCH₂Ph), 4.71 (d, J = 4.4 Hz, 1H, H5), 4.60-4.35 (m, 5H, OCH₂Ph), 4.19 (t, J = 6.4 Hz, 1H, H2), 3.80 (s, 1H, H3), 3.78 (s, 3H, ArOMe), 3.66 (dd, J = 11.1, 2.4 Hz, 1H, H4), 3.60 (t, J = 6.3 Hz, 2H, CH₂0), 3.55 (s, 3H, OMe), 3.31 - 3.24 (m, 1H, H4a). ¹³C NMR (101 MHz, CDCI₃) δ 160.56, 153.13, 139.03, 138.97, 138.15, 128.61, 128.43, 128.40, 128.12, 127.96, 127.75, 127.52, 127.14, 114.73, 107.86, 100.74, 97.96, 76.04, 75.67, 75.16, 74.05, 73.72, 72.86, 71.82, 69.18, 56.99, 55.55, 34.91, 29.92. [a]_D ²⁰= -2,2 (c=1, CHCI₃); MS: m/z calculated [M + Na]⁺ = 605.3, [M + K]⁺ = 621.2; measured [M + Na]⁺ = 605.6, [M + K]⁺ = 621.5.

(5S)

¹H NMR (400 MHz, CDCI₃) δ 7.39 - 7.16 (m, 15H, Ar), 6.97 (d, J = 8.4 Hz, 1H, H6), 6.47 (dd, J = 8.3, 2.5 Hz, 1H, H7), 6.43 (d, J = 2.3 Hz, 1H, H8), 5.71 (d, J = 3.2 Hz, 1H, MOa), 4.97 -4.87 (d, J = 11.4 Hz, 1H, OCH₂Ph), 4.65-4.43 (m, 5H, OCH₂Ph), 4.37 (d, J = 2.1 Hz, 1H, H5), 4.19 (d, J = 5.5 Hz, 1H, H2), 3.98 (s, 1H, H3), 3.77 (s, 3H, ArOMe), 3.70 - 3.63 (m, 2H,CH₂0), 3.35 (s, 3H, OMe), 3.32 (d, J = 2.4 Hz, 1H, H4), 3.00 (m, 1H, H4a).¹³C NMR (101 MHz, CDCI₃) δ 161.44, 155.01, 138.80, 138.10, 137.84, 131.97, 128.67, 128.65, 128.50, 128.25, 128.20, 128.03, 128.02, 127.84, 111.11, 108.00, 101.38, 95.17, 75.34, 74.78, 74.35, 73.79, 71.70, 71.60, 71.57, 69.00, 56.13, 55.54, 37.84, 29.93. [a]_D ²⁰= -4,6 (c=1, CHCI₃). MS: m/z calculated [M + Na]⁺ = 605.3, [M + K]⁺ = 621.2; measured [M + Na]⁺ = 605.7, [M + K]⁺ = 621.6.

(2R,3R,4R,4aR,5R,10aR)-3,4-bis(benzyloxy)-2-(benzyloxymethyl)-8-methyl-5- methoxy-2,3,4,4a,5,10a-hexahydropyran[2,3-b]chromene (compound 09): yield 45%, C5 R/S 100/0

¹H NMR (400 MHz, CDCI₃) δ 7.42 (d, J = 7.8 Hz, 1H, H6), 7.37 - 7.20 (m, 15H, Ar), 6.81 (d, J = 7.8 Hz, 1H, H7), 6.66 (s, 1H, H9), 5.63 (d, J = 2.8 Hz, 1H, MOa), 4.97 (d, J = 11.4 Hz, 1 H, OCH₂Ph), 4.74 (d, J = 4.2 Hz, 1 H, H5), 4.62 - 4.34 (m, 5H, OCH₂Ph), 4.19 (t, J = 6.3 Hz, 1H, H2), 3.81 (s, 1H, H3), 3.66 (dd, J = 11.1, 2.6 Hz, 1H, H4), 3.62 (dd, J = 6.2, 4.6 Hz, 2H, CH₂0), 3.56 (s, 3H, OMe), 3.34 - 3.21 (m, 1H, H4a), 2.31 (s, 3H, Me). ¹³C NMR (101 MHz, CDCI₃) δ 152.11, 139.20, 139.07, 139.00, 138.19, 128.61, 128.44, 128.41, 128.37, 128.12, 127.97, 127.94, 127.75, 127.51, 126.10, 122.28, 119.48, 116.04, 97.74, 76.22, 75.74, 75.16, 74.03, 73.70, 72.84, 71.69, 69.16, 57.06, 34.89, 21.41. [a]_D ²⁰= -6,2 (c=1, CHCI₃). MS: m/z calculated [M + K]⁺ = 605.2; measured [ [M + K]⁺ = 605.2.

(2R,3S,4R, 4aR,5R,10aR)-3,4-bis(benzyloxy)-2-(benzyloxymethyl)-7-methyl-5- methoxy-2,3,4,4a,5,10a-hexahydropyran[2,3-b]chromene (compound 10): yield 66%, C5 R/S 100/0

¹H NMR (400 MHz, CDCI₃) δ 7.43 - 7.18 (m, 14H, Ar and H6), 7.09 (dd, J = 6.7, 2.7 Hz, 2H, Ar), 6.99 (d, J = 6.3 Hz, 1H, H8), 6.72 (d, J = 8.2 Hz, 1H, H9), 5.60 (d, J = 3.0 Hz, 1H, MOa), 4.82 (d, J = 10.7 Hz, 1H, OCH₂P ), 4.74 (d, J = 4.4 Hz, 1H, H5), 4.71 - 4.44 (m, 5H, OCH₂Ph), 4.07 (d, J = 9.9 Hz, 1H, H2), 3.86 - 3.79 (m, 2H, CH₂0), 3.74 (dd, J = 10.8, 1.9 Hz, 1H, H3), 3.72-3.65 (m, 1H, H4), 3.55 (s, 3H, OMe), 2.83 (ddd, J = 10.5, 4.4, 3.2 Hz, 1H, H4a), 2.30 (s, 3H, Me).¹³C NMR (101 MHz, CDCI₃) δ 149.83, 139.14, 138.40, 138.19, 130.78, 129.78, 128.61, 128.58, 128.44, 128.17, 128.01, 127.91, 127.89, 127.55, 126.48, 121.83, 115.50, 97.17, 78.56, 78.54, 76.43 , 75.60, 74.92, 73.77, 72.55, 68.67, 57.39, 40.09, 20.98. [a]_D ²⁰= +3,7 (c=1, CHCI₃). MS: m/z calculated [M + Na]⁺= 589.3, [M + K]⁺= 605.2; measured [M + Na]⁺= 589.4, [M + K]⁺ = 605.3. (2R,3S,4R, 4aR,5R,10aR)-3,4-bis(benzyloxy)-2-(benzyloxymethyl)-5,8-dimethoxy- 2,3,4,4a,5,10a-hexahydropyran[2,3-b]chromene (compound 11 ): yield 37%, C5 R/S 100/0

¹H NMR (400 MHz, CDCI₃) δ 7.43 (d, J = 8.6 Hz, 1 H, H6), 7.38 - 7.19 (m, 10H, Ar), 7.15 - 7.05 (m, 2H, Ar), 6.56 (dd, J = 8.5, 2.3 Hz, 1 H, H7), 6.40 (t, J = 5.9 Hz, 1 H, H9), 5.61 (d, J = 2.8 Hz, 1 H, H10a), 4.83 (d, J = 10.6 Hz, 1 H, H4a), 4.72 (d, J = 4.4 Hz, 1 H, OCH₂Ph), 4.70-4.44 (m, 5H, OCH₂Ph), 4.08 (d, J = 10.0 Hz, 1 H, H2), 3.88 - 3.73 (m, 3H, H3 and CH₂0), 3.79 (s, 3H, OMe), 3.73 - 3.65 (m, 1 H, H4), 3.52 (s, 3H, OMe), 2.89 - 2.75 (m, 1 H, H4a). ¹³C NMR (101 MHz, CDCI₃) δ 160.66, 152.96, 139.13, 138.37, 138.18, 128.62, 128.60, 128.44, 128.18, 128.15, 128.02, 127.93, 127.91 , 127.56, 127.12, 1 14.56, 108.09, 100.84, 97.50, 78.51 , 78.45, 76.18, 75.63, 74.97, 73.78, 72.70, 68.67, 57.29, 55.57, 40.20. [a]_D ²⁰= +1 1 ,6 (c=1 , CHCI₃). MS: m/z calculated [M + Na]⁺ = 605.3, [M + K]⁺ = 621 .2; measured [M + Na]⁺ = 605.6, [M + K]⁺ = 621 .4.

(2R,3S,4R,4aR,5R,10aR)-3,4-bis(benzyloxy)-2-(benzyloxymethyl)-8-methyl-5- methoxy-2,3,4,4a,5,10a-hexahydropyran[2,3-b]chromene (compound 12): yield 21 %, C5 R/S 100/0

¹H NMR (400 MHz, CDCI₃) δ 7.41 (d, J = 7.9 Hz, 1 H, H6), 7.39 - 7.18 (m, 13H, Ar), 7.14 - 7.03 (m, 2H, Ar), 6.80 (d, J = 7.7 Hz, 1 H, H7), 6.65 (s, 1 H, H9), 5.62 (d, J = 2.7 Hz, 1 H, H10a), 4.82 (d, J = 10.6 Hz, 1 H, OCH₂Ph), 4.74 (d, J = 3.8 Hz, 1 H, H5), 4.72 - 4.39 (m, 5H, OCH₂Ph), 4.07 (d, J = 10.0 Hz, 1 H, H2), 3.89 - 3.72 (m, 3H, H3 and CH₂0), 3.68 (t, J = 9.7 Hz, 1 H, H4), 3.53 (s, 3H, OMe), 2.87 - 2.78 (m, 1 H, H4a), 2.30 (s, 3H, Me). ¹³C NMR (101 MHz, CDCI₃) δ 151.94, 139.37, 139.14, 138.39, 138.20, 128.62, 128.59, 128.44, 128.17, 128.02, 127.92, 127.90, 127.55, 126.05, 122.43, 1 19.33, 1 16.17, 97.28, 78.52, 76.93, 76.34, 75.61 , 74.96, 73.77, 72.58, 68.68, 57.33, 40.17, 21 .38. [a]_D ²⁰= +8,3 (c=1 , CHCI₃). MS: m/z calculated [M + Na]⁺

K]⁺ = 605.2; measured [M + Na]⁺ = 589.5, [M + K]⁺ = 605.2.

Deprotected compounds 13-22

(2R,3R,4R,4aS,5R,10aR)-2-(hydroxymethyl)-5-methoxy-2,3,4,4a,5,10a

hexahydropyran[2,3-b]chromene-3,4-diol (compound 13): yield 97%

¹H NMR (400 MHz, CD₃OD) δ 7.45 (d, J = 7.7 Hz, 1 H, H6), 7.18 (t, J = 7.7 Hz, 1 H, H8), 6.94 (dd, J = 17.4, 9.9 Hz, 1 H, H7), 6.78 (d, J = 8.2 Hz, 1 H, H9), 5.62 (d, J = 3.1 Hz, 1 H, H10a), 4.91 (d, J = 2.4 Hz, 1 H, H5), 3.99 (t, J = 6.0 Hz, 1 H, H2), 3.81 (s, 2H, H3 and H4), 3.80 - 3.74 (m, 2H, CH₂0), 3.69 (s, 3H, OMe), 3.00 - 2.92 (m, 1 H, H4a). ¹³C NMR (101 MHz, CD₃OD) δ 156.35, 132.98, 130.04, 125.32, 124.83, 1 19.22, 100.69, 81.51 , 76.68, 71 .54, 71 .23, 65.57, 61 .65, 38.46. [a]_D ²⁰= -7,6 (c=1 , CH₃CH₂OH); MS: m/z calculated [M + Na]⁺ = 305.1 , [M + K]⁺ = 321.1 ; measured [M + Na]⁺ = 305.3, [M + K]⁺ = 321 .2.

(2R,3R,4R,4aS,5R,10aR)-7-amino-2-(hydroxymethyl)-5-methoxy-2,3,4,4a,5,10a- hexahydropyran[2,3-b]chromene-3,4-diol (compound 14): yield 94%

¹H NMR (400 MHz, CD₃OD) δ 6.89 (s, 1 H, H6), 6.65-6.55 (m, 2H, H8 and H9), 5.52 (d, J = 3.0 Hz, 1 H, H10a), 4.83 (d, J = 4.9 Hz, 1 H, H5), 3.98 (t, J = 5.8 Hz, 1 H, H2), 3.87 - 3.78 (m, 2H, H3 and H4), 3.79 - 3.73 (m, 1 H, CH₂0), 3.67 (s, 3H, OMe), 2.96 - 2.85 (m, 1 H, H4a). ¹³C NMR (101 MHz, CD₃OD) δ 149.10, 144.77, 125.69, 121 .06, 1 19.69, 1 18.60, 1 17.30, 1 14.55, 100.39, 81 .79, 80.99, 76.53, 71.56, 71.43, 65.59, 61.71 , 38.72. [a]_D ²⁰= +13,3 (c=1 , CH₃CH₂OH). MS: m/z calculated [M + H]⁺ = 298.1 [M + Na]⁺ = 320.1 , [M + K]⁺ = 336.1 ; measured [M + H]⁺ = 298.3, [M + Na]⁺ = 320.3, [M + K]⁺ = 336.3.

(2R,3R,4R,4aS,5R,10aR)-2-(hydroxymethyl)-5-methoxy-2,3,4,4a,5,10a- hexahydropyran[2,3-b]chromene-3,4,7-triol (compound 15): yield 100%

¹H NMR (400 MHz, CD₃OD) δ 6.88 (s, 1H, H6), 6.62 (s, 2H, H8 and H9), 5.54 (d, J = 2.8 Hz, 1H, H10a), 4.84 (d, J = 4.8 Hz, 1H, H5), 3.98 (t, J = 5.9 Hz, 1H, H2), 3.84 (d, J = 2.7 Hz, 1H, H4), 3.81 (s, 1H, H3), 3.76 (dd, J = 5.8, 2.3 Hz, 2H, CH₂0), 3.68 (s, 3H, OMe), 2.98 - 2.84 (m, 1H, H4a).¹³C NMR (101 MHz, CD₃OD) δ 155.33, 149.19, 125.97, 119.88, 119.77, 116.18, 116.06, 100.47, 81.66, 76.55, 71.57, 71.35, 65.59, 61.67, 38.61. [a]_D ²⁰= +11,1 (c=1 , CH₃CH₂OH); MS: m/z calculated [M + Na]⁺ = 321.1 ; measured [M + Na]⁺ = 321.2.

(2R,3R,4R,4aS,5R,10aR)-2-(hydroxymethyl)-5,7-dimethoxy-2,3,4,4a,5,10a- hexahydropyran[2,3b]chromene-3,4-diol (compound 16): yield 96%

¹H NMR (400 MHz, CD₃OD) δ 7.00 (d, J = 2.1 Hz, 1H, H6), 6.77 (dd, J = 8.9, 2.3 Hz, 1H, H8), 6.71 (d, J = 8.8 Hz, 1H, H9), 5.57 (d, J = 3.0 Hz, 1H, H10a), 4.87 (s, 1H, H5), 3.98 (t, J = 6.0 Hz, 1H, H2), 3.83 - 3.79 (m, 2H, H3 and H4), 3.76 (dd, J = 6.1, 3.0 Hz, 2H, CH₂0), 3.74 (s, 3H, OMe), 3.68 (s, 3H, OMe), 2.98 - 2.89 (m, 1H, H4a).¹³C NMR (101 MHz, CD₃OD) δ 158.33, 150.09, 125.97, 119.98, 118.90, 114.61, 100.59, 81.54, 76.60, 71.60, 71.26, 65.57, 61.52, 58.83, 38.47. [a]_D ²⁰= +8,9 (c=1, CH₃CH₂OH); MS: m/z calculated [M + Na]⁺ = 335.1 ; measured [M + Na]⁺ = 335.3. (2R,3R,4R,4aS,5R,10aR)-2-(hydroxymethyl)-7-methyl-5-methoxy-2,3,4,4a,5,10a- hexahydropyran[2,3-b]chromene-3,4-diol (compound 17): yield 95%

¹H NMR (400 MHz, CD₃OD) δ 7.24 (s, 1H, H6), 6.98 (d, J = 8.2 Hz, 1H, H8), 6.66 (d, J = 8.3 Hz, 1H, H9), 5.57 (d, J = 3.0 Hz, 1H, H10a), 3.98 (t, J = 6.0 Hz, 1H, H2), 3.83 - 3.78 (m, 2H, H3 and H4), 3.77 (dd, J = 6.0, 2.9 Hz, 2H, CH₂0), 3.68 (s, 3H, OMe), 2.96 - 2.89 (m, 1 H, H4a), 2.26 (s, 3H, Me). ¹³C NMR (101 MHz, CD₃OD) δ 150.14, 130.22, 129.54, 126.29, 120.97, 1 15.09, 96.65, 77.67, 72.66, 67.62, 67.37, 61 .64, 57.73, 34.59, 19.57. [a]_D ²⁰= +13,3 (c=1 , CH₃CH₂OH); MS: m/z calculated [M + Na]⁺ = 319.1 , [M + K]⁺ = 335.1 ; measured [M + Na]⁺ = 319.4, [M + K]⁺ = 335.4.

(2R,3R,4R,4aS,5R,10aR)-2-(hydroxymethyl)-5,8-dimethoxy-2,3,4,4a,5,10a- hexahydropyran[2,3-b]chromene-3,4-diol (compound 18): yield 97%

¹H NMR (400 MHz, CD₃OD) δ 7.32 (d, J = 8.6 Hz, 1 H, H6), 6.54 (dd, J = 8.6, 2.4 Hz, 1 H, H7), 6.35 (d, J = 2.4 Hz, 1 H, H9), 5.58 (d, J = 3.0 Hz, 1 H, H10a), 4.84 (d, J = 4.9 Hz, 1 H, H5), 4.00 (t, J = 6.0 Hz, 1 H, H2), 3.86 - 3.79 (m, 2H, H3 and H4), 3.77 (dd, J = 6.0, 3.3 Hz, 2H, CH₂0), 3.74 (s, 3H, OMe), 3.67 (s, 3H, OMe), 2.96-2.86 (m, 1 H, H4a). 1³C NMR (101 MHz, CD₃OD) δ 160.95, 153.28, 126.97, 1 13.53, 107.31 , 100.40, 96.94, 77.53, 72.80, 67.62, 67.29, 61 .64, 57.61 , 54.54, 34.63. [a]_D ²⁰= -7,6 (c=1 , CH₃CH₂OH); MS: m/z calculated [M + Na]⁺ = 335.1 , [M + K]⁺ = 351.1 ; measured [M + Na]⁺ = 335.4, [M + K]⁺ = 351 .3.

(2R,3R,4R,4aS,5R,10aR)-2-(hydroxymethyl)-8-methyl-5-methoxy-2,3,4,4a,5,10a- hexahydropyran[2,3-b]chromene-3,4-diol (compound 19): yield 97%

¹H NMR (400 MHz, CD₃OD) δ 7.29 (d,J = 7.8 Hz, 1 H, H6), 6.76 (d, J = 7.8 Hz, 1 H, H7), 6.60 (s, 1 H, H9), 5.57 (d, J = 3.0 Hz, 1 H, H10a), 4.85 (d, J = 4.7 Hz, 1 H, H5), 3.98 (t, J = 5.9 Hz, 1 H, H3), 3.83 - 3.73 (m, 4H, CH₂0, H2, H4), 3.67 (s, 3H, OMe), 2.96 - 2.85 (m, 1 H, H4a), 2.25 (s, 3H, Me).

¹³C NMR (101 MHz, CD₃OD) δ 156.14, 143.22, 133.19, 129.62, 125.66, 122.29, 1 19.72, 100.65, 81.54, 76.64, 71 .24, 65.63, 61 .61 , 38.51 , 23.91 . [a]_D ²⁰= +8,3 (c=1 , CH₃CH₂OH); MS: m/z calculated [M + Na]⁺ = 319.1 ; measured [M + Na]⁺ = 319.3. (2R,3S,4R,4aS,5R,10aR)-2-(hydroxymethyl)-7-methyl-5-methoxy-2,3,4,4a,5,10a- hexahydropyran[2,3-b]chromene-3,4-diol (compound 20): yield 98%

¹H NMR (400 MHz, CD₃OD) δ 7.12 (s, 1 H, H6), 6.85 (d, J = 8.3 Hz, 1 H, H8), 6.54 (d, J = 8.3 Hz, 1 H, H9), 5.38 (d, J = 2.9 Hz, 1 H, M Oa), 3.75 - 3.59 (m, 3H, CH₂0 and H2), 3.53 (s, 4H, H3 and OMe), 3.34 (t, J = 8.9 Hz, 1 H, H4), 2.50 - 2.40 (m, 1 H, H4a), 2.13 (s, 3H, Me). ¹³C NMR (101 MHz, CD₃OD) δ 150.01 , 130.29, 129.54, 126.43, 121 .13, 1 15.15, 96.39, 77.56, 73.82, 70.37, 70.10, 61 .29, 57.52, 40.03, 19.56. [a]_D ²⁰= +13,3 (c=1 , CH₃CH₂OH); MS: m/z calculated [M + K]⁺ = 335.1 ; measured [M + K]⁺ = 335.3.

(2R,3S,4R,4aS,5R,10aR)-2-(hydroxymethyl)-5,8-dimethoxy-2,3,4,4a,5,10a- hexahydropyran[2,3-b]chromene-3,4-diol (compound 21 ): yield 97%

¹H NMR (400 MHz, CD₃OD) δ 7.33 (d, J = 8.6 Hz, 1 H, H6), 6.54 (dd, J = 8.6, 2.4 Hz, 1 H, H7), 6.36 (d, J = 2.4 Hz, 1 H, H9), 5.51 (t, J = 6.6 Hz, 1 H, H10a), 4.83 (d, J = 4.8 Hz, 1 H, H5), 3.87 - 3.66 (m, 6H, CH₂0 and H4 and OMe), 3.66 (d, J = 6.3 Hz, 3H, OMe), 3.48 (t, J = 9.2 Hz, 1 H, H3), 2.57 (ddd, J = 10.3, 4.9, 3.1 Hz, 1 H, H4a). ¹³C NMR (101 MHz, CD₃OD) δ 160.95, 153.13, 127.12, 1 13.68, 107.43, 100.38, 96.66, 77.40, 73.93, 70.26, 70.02, 61.24, 57.39, 54.54, 40.05. [a]_D ²⁰= +1 1 ,6 (c=1 , CH₃CH₂OH); MS: m/z calculated [M + Na]⁺ = 335.1 , [M + K]⁺ = 351.1 ; measured [M + Na]⁺ = 335.5, [M + K]⁺ = 351.5.

(2R,3S,4R,4aS,5R,10aR)-2-(hydroxymethyl)-8-methyl-5-methoxy-2,3,4,4a,5,10a- hexahydropyran[2,3-b]chromene-3,4-diol (compound 22): yield 98%

¹H NMR (400 MHz, CD₃OD) δ 7.31 (d, J = 7.8 Hz, 1H, H6), 6.78 (d, J = 7.7 Hz, 1H, H7), 6.62 (s, 1H, H9), 5.52 (d, J = 2.9 Hz, 1H, MOa), 4.85 (d, J = 4.7 Hz, 1H, H5), 3.85 (dd, J = 13.7, 4.5 Hz, 1H, CH₂0), 3.76 (q, J = 4.2 Hz, 2H, CH₂0 and H2), 3.68 - 3.62 (m, 4H, H4 and OMe), 3.48 (t, J = 9.0 Hz, 1H, H3), 2.58 (ddd, J = 10.4, 4.9, 3.1 Hz, 1H, H4a), 2.27 (s, 3H, Me).¹³C NMR (101 MHz, CD₃OD) δ 152.07, 139.31, 126.11, 121.84, 118.54, 115.68, 96.45, 77.50, 73.84, 70.30, 70.04, 61.25, 57.47, 40.04, 19.99. [a]_D ²⁰=-7,8 (c=1, CH₃CH₂OH); MS: m/z calculated [M + Na]⁺= 319.1, [M + K]⁺= 335.1; measured [M + Na]⁺ = 319.4, [M + K]⁺ = 335.3.

Synthesis of the fluorescent compound 26

(2R,3S,4R,4aS,5R,10aR)-7-methyl-5-methoxy-2-tosilossimethyl-2,3,4,4a,5,10a- hexahydropyran[2,3-b]chromene-3,4-diol (compound 23): yield 95%

¹H NMR (400 MHz, CDCI₃) δ 7.83 (d, J = 8.2 Hz, 2H,ArOTs), 7.34 (d, J = 8.0 Hz, 2H, ArOTs), 7.19 (s, 1H,H6), 7.01 (d, J = 8.2 Hz, 1H, H8), 6.71 (d, J = 8.3 Hz, 1H, H9), 5.46 (d, J = 2.8 Hz, 1H, H10a), 4.76 (d, J = 5.0 Hz, 1H, H5), 4.39 - 4.21 (m, 2H, CH20), 3.94 (m, 2H, H4 and H2), 3.83 (s, 1H, H3), 3.69 (s, 3H, OMe), 2.82 (m, 1H, H5a), 2.44 (s, 3H, Me), 2.29 (s, 3H, Me).¹³C NMR (101 MHz, cdcl₃) δ 149.60, 145.05, 133.05, 131.06, 130.51, 130.05, 128.31, 126.68, 120.04, 116.11, 95.95, 78.50, 77.54, 77.22, 76.91, 69.55, 68.98, 66.88, 66.63, 59.64, 34.70, 21.85, 20.87. [a]_D ²⁰= +4,1 (c=1, CH₃CH₂OH); MS: m/z calculated [M + Na]⁺ = 473.5; measured [M + Na]⁺ = 473.1

(2R,3S,4R,4aS,5R,10aR)-2-azidomethyl-7-methyl-5-methoxy-2,3,4,4a,5,10a- hexahydropyran[2,3-b]chromene-3,4-diol (compound 24): yield 60%

¹H NMR (400 MHz, CDCI₃) δ 7.22 (s, 1H, H6), 7.02 (d, J = 7.9 Hz, 1H, H8), 6.75 (d, J = 8.3 Hz, 1H, H9), 5.56 (d, J = 2.7 Hz, 1H, MOa), 4.80 (d, J = 5.0 Hz, 1H, H5), 4.16 (t, J = 6.4 Hz, 1H, H2), 3.98 (d, J = 2.9 Hz, 1H, H4), 3.83 (s, 1H, H3), 3.72 (s, 3H, OMe), 3.71 - 3.66 (m, 1H, CH₂0), 3.51 (dd, J = 12.7, 5.4 Hz, 1H, CH₂0), 2.93-2.84 (m, 1H, H5a), 2.30 (s, 3H,Me).¹³C NMR (101 MHz, CDCI₃) δ 149.67, 131.05, 130.53, 126.71, 120.06, 116.14, 96.06, 78.53, 77.57, 77.25, 76.93, 70.67, 67.25, 67.15, 59.72, 51.50, 34.69, 20.92. [a]_D ²⁰= -10,3 (c=1, CH₃CH₂OH); MS: m/z calculated [M + Na]⁺ = 344.3; measured [M + Na]⁺ = 344.1

(2R,3S,4R,4aS,5R,10aR)-2-aminomethyl-7-methyl-5-methoxy-2,3,4,4a,5,10a- hexahydropyran[2,3-b]chromene-3,4-diol (compound 25):

¹H NMR (400 MHz, CD₃OD) δ 7.23 (d, J = 16.4 Hz, 1H, H6), 6.98 (d, J = 8.1 Hz, 1H, H8), 6.64 (dd, J = 8.2, 2.4 Hz, 1H, H9), 5.59 (d, J = 3.0 Hz, 1H, MOa), 4.86 (d, J = 5.0 Hz, 1 H, H5), 3.95 (dd, J = 7.3, 4.8 Hz, 1 H, H2), 3.88 - 3.77 (m, 1 H, H4), 3.74 (dd, J = 9.7, 5.3 Hz, 1H, H3), 3.68 (s, 3H, OMe), 3.06 - 3.00 (m, 1H, CH20), 2.97 - 2.90 (m, 1H, H5a), 2.87 (dd, J = 13.3, 4.5 Hz, 1H, CH20), 2.29-2.23 (m, 3H, Me).

{N-[((2R,3R,4R,4aS,5R,10aR)-3,4-dihydroxy-5-methoxy-7-methyl-2,3,4,4a,5,10a- hexahydropyran[2,3-b]chromen-2-il]methyl}-2-(7-hydroxycumaril)acetamide (compound 26): 43 %(2 steps)

¹H NMR (400 MHz, CD₃OD) δ 7.59 (d, J = 8.8 Hz, 1 H, H5'), 7.23 (s, 1 H, H6), 6.97 (d, J = 7.5 Hz, 1 H, H8), 6.76 (d, J = 8.7 Hz, 1 H, H6'), 6.63 (m, 2H,H9 and H8' ), 6.16 (s, 1 H, H3'), 5.54 (d, J = 2.8 Hz, 1 H, H10a), 4.85 (d, J = 4.9 Hz, 1 H, H5), 4.02 (s, 1 H, H2), 3.81 -3.71 (m, 3H, H4 and CH2C=0), 3.67 (s, 4H, OMe and H3), 3.57 (dd, J = 13.8, 4.5 Hz, 1 H, CH20), 3.44 (dd, J = 13.5, 8.5 Hz, 1 H.CH20), 2.88 (m, 1 H, H5a), 2.26 (s, 3H, Me).¹³C NMR (101 MHz, CD30D) δ 170.35, 162.86, 156.03, 150.04, 130.21 , 129.55, 126.27, 126.16, 120.88, 1 15.22, 1 14.65, 1 10.71 , 1 10.37, 102.95, 96.59, 77.58, 70.49, 68.05, 67.12, 67.00, 57.64, 48.44, 48.23, 48.02, 47.81 , 47.59, 47.38, 47.17, 40.72, 34.36, 29.59, 19.57. [a]_D ²⁰= +16,6 (c=1 , CH₃CH₂OH); MS: m/z calculated [M + Na]⁺ = 520.5; measured [M + Na]⁺ = 520.2

Description of figures

Twenty figures are enclosed to the present description.

Figure 1 shows a synthesis scheme of the compounds 3-12.

Figure 2 shows a deprotection scheme of the products 3-12 to give the products 13- 22.

Figure 3 shows ¹H spectra of the compounds 13-22 solubilized in deuterated PBS at 25°C (A, compound 13; C, compound 14; E, compound 15; G, compound 16; I, compound 17; M, compound 18; O, compound 19; Q, compound 20; S, compound 21 and U, compound 22) and 1 D-STD spectra of the mixtures dissolved in deuterated PBS at 25°C containing the Αβ1-42 peptide (80 uM) and one of the compounds under examination (1.6 mM) (B, compound 13; D, compound 14; F, compound 15; H, compound 16; L, compound 17; N, compound 18; P, compound 19; R, compound 20; T, compound 21 ; V, compound 22). The ¹H spectra were acquired with 64 scanning procedures, the 1 D-STD spectra with 512 scanning procedure and 2 s of saturation of the peptide resonances. The figure summarizes the results of the STD-NMR experiments carried out on mixtures ligand: peptide 20:1 in deuterated PBS at 25°C. Each mixture was analyzed by selectively irradiating the sample at -1.0 ppm, spectral region wherein no proton of our compounds resonates and, on the contrary, it results effective in order to obtain the selective saturation of the peptide resonances in oligomeric form. The appearance of signals of the compound in the STD spectrum acquired on the mixture demonstrates the existence of an interaction of the same with the peptide; viceversa, the absence of molecule signal is an index of the lack of linkage. Except from the compound 14, in case thereof the molecule signals are almost absent in the STD spectrum (Figure 3D), all other molecules show STD effect, demonstrating the capability thereof to recognize and link the Αβ1 -42 peptide.

Figure 4 shows 2D-NOESY spectra of the compounds 14 (A) and 17 (B) solubilized in PBS, pH 7.5, 25°C, mixing time 0.9 s. trNOESY of mixtures containing Αβ1-42 (80 uM) and the compound 14 (C) or the compound 17 (D) dissolved under the same conditions, mixing time 0.3 s. The positive cross-peaks are shown in dark grey, the positive ones in light grey.

In the trNOESY spectra, a change of sign of the cross-peaks of a molecule with low molecular weight, such as the compounds constituting out library, sign which from positive, in absence of peptide, becomes negative in presence of the same, designates an increase in the molecule correlation time due to the interaction with Αβ1 -42; such sign variation then constitutes an additional linkage evidence. The trNOESY spectra of the compounds 13-22 showed a sign inversion of the cross-peaks of the molecules, except from the compound 14 which, according to what indicated by the STD experiments, does not result to link the Αβ1-42 peptide with an affinity comparable to that of the other molecules constituting the library.

Figure 5 shows the fractional STD effects calculated for the compounds 13, 15, 17,

18, 19, 20, 21 and 22 and related to the linkage affinity to the Αβ1 -42 peptide.

As the intensity of the STD signals of a molecule is directly proportional to the linkage affinity to the molecular target, we used this type of experiment even in order to determine the relative affinity of the molecules 13, 15, 17, 18, 19, 20, 21 and 22 for the same peptide through competitive STD experiments. Due to the overlapping of the resonances of the compounds, it resulted to be impossible to produce one single mixture containing all compounds under examination. For this reason three different competitive STD experiments were performed, one for the molecules containing the saccharidic mojety deriving from the D-galactose (compounds 13-19), one for the molecules containing the saccharidic mojety deriving from the D-glucose (compounds 20-22) and one to compare two best ligands of the two previous series (compounds 17 and 20). In the first two experiments the STD effect related to the H6 proton of each compound was evaluated; in the third experiment the STD effect related to the H10a proton was evaluated. In particular, the fractional STD effect was calculated as (lo-l)/lo_> wherein I is the intensity of the peak of signal checked in the STD spectrum and l₀ is the intensity of the same signal in the reference spectrum. The third competition experiment revealed that the compounds 17 and 20 show the same affinity for the Αβ1 -42 peptide, as the H10a protons of the two molecules have the same fractional STD effect. For this reason, in order to compare the data obtained in the first two competitive experiments, their fractional STD effect was placed equal to 1 and then the relative intensities of other molecules were determined. The obtained results are summarized in Figure 5. The graph shows inequivocably that the compounds 17, 19, 20 and 22, which have as substituent on the aromatic ring a methyl group, are the ligands with highest affinity for the Αβ1-42 peptide; the compounds 16, 18 and 21 follow, having as substituent a methoxyl group and together with the compound 13, without substituents on the aromatic ring, have a relative fractional STD effect equal to little more than 70%; the compound 15, at last, wherein a group OH is present in position 7, is the less similar of the series. This last piece of data, together with the absence of linkage by the amine 14, clearly shows that the greater is the apolarity of the substituent existing on the benzylic ring, the greater is the affinity of the compound for Αβ1-42. At the same time, the substituent position on the aromatic ring (7 or 8), so like the nature of the saccharidic entity, result to be uninfluential with respect to the interaction, as demonstrated by the fact that the compounds 17, 19, 20 and 22 and the compounds 16, 18 and 21 show the same affinity.

Figure 6 shows A ¹H NMR Specrtum of the mixture containing the Αβ1-42 peptide (80 uM) and the compound 17 (1 .6 mM) in PBS, pH=7.5, 25°C; B-F STD-NMR spectra acquired on the same mixture with different saturation time (B, 0.5 s; C, 1 ,2 s; D, 2,0 s; E 3,0 s; F, 5,0 s).

The linkage epitope of our compounds was determined through the same STD experiments, which, for each molecule, were performed with different saturation time (0,5, 1 ,2; 2,0; 3,0; 5,0 s) (Figure 6). For all ligands, the region mostly involved in the linkage results to be the aromatic ring, whereas the saccharidic portion is the one showing the less intense STD signals. This explains why the stereochemistry of the oxydrilic groups of the latter does not influence the affinity and, on the contrary, the polarity of the substituents existing on the aromatic entity on the contrary is decisive; the polar substituents, in fact, as previously shown, results to be unfavourable for the interaction, contrary to the apolar substituents promoting it.

Figure 7 shows the overlapping of the 30 structures with lowest energy obtained by means of MD simulations in water, 298K; A, compound 13; B, compound 14; C, compound 15; D, compound 16; E, compound 17; F, compound 18; G, compound 19; H, compound 20; I, compound 21 ; L, compound 22

Figure 8 shows the distance H2-H3 (A) for each one of the calculated structures. A, compound 13; B, compound 14; C, compound 15; D, compound 16; E, compound 17; F, compound 18; G, compound 19; H, compound 20; I, compound 21 ; L, compound 22.

Figure 9 shows the distance H2-H4 (A) for each one of the calculated structures. A, compound 13; B, compound 14; C, compound 15; D, compound 16; E, compound 17; F, compound 18; G, compound 19; H, compound 20; I, compound 21 ; L, compound 22.

Figure 10 shows the distance H3-H4 (A) for each one of the calculated structures. A, compound 13; B, compound 14; C, compound 15; D, compound 16; E, compound 17; F, compound 18; G, compound 19; H, compound 20; I, compound 21 ; L, compound 22 Figure 11 shows the distance H4a-H10a (A) for each one of the calculated structures. A, compound 13; B, compound 14; C, compound 15; D, compound 16; E, compound 17; F, compound 18; G, compound 19; H, compound 20; I, compound 21 ; L, compound 22.

Figure 12 shows the distance H4a-H5 (A) for each one of the calculated structures. A, compound 13; B, compound 14; C, compound 15; D, compound 16; E, compound 17; F, compound 18; G, compound 19; H, compound 20; I, compound 21 ; L, compound 22.

Figure 13 shows the distance H10a-H5 (A) for each one of the calculated structures. A, compound 13; B, compound 14; C, compound 15; D, compound 16; E, compound 17; F, compound 18; G, compound 19; H, compound 20; I, compound 21 ; L, compound 22.

Figure 14 shows the dihedral angle H2-C2-C3-H3 (°) for each one of the calculated structures. A, compound 13; B, compound 14; C, compound 15; D, compound 16; E, compound 17; F, compound 18; G, compound 19; H, compound 20; I, compound 21 ; L, compound 22.

Figure 15 shows the dihedral angle H3-C3-C4-H4 (°) for each one of the calculated structures. A, compound 13; B, compound 14; C, compound 15; D, compound 16; E, compound 17; F, compound 18; G, compound 19; H, compound 20; I, compound 21 ; L, compound 22.

Figure 16 shows the dihedral angle H4a-C4a-C10a-H10a (°) for each one of the calculated structures. A, compound 13; B, compound 14; C, compound 15; D, compound 16; E, compound 17; F, compound 18; G, compound 19; H, compound 20; I, compound 21 ; L, compound 22.

Figure 17 shows the dihedral angle H4a-C4a-C5-H5(°) for each one of the calculated structures. A, compound 13; B, compound 14; C, compound 15; D, compound 16; E, compound 17; F, compound 18; G, compound 19; H, compound 20; I, compound 21 ; L, compound 22.

The conformational analysis carried out by means of simulations of molecular mechanics (MM) and molecular dynamicse (MD) showed that the affinity differences for Αβ1-42 peptide are mainly due to this factor and they cannot be ascribed in any way to conformational features of the compounds themselves. All ten molecules 13-22, in fact, have the same conformation, as it results evident from Figure 7. As additional demonstration of these data, the values related to the distances H2-H3 (Figure 8), H2- H4 (Figure 9), H3-H4 (Figure 10), H4a-H10a (Figure 1 1 ), H4a-H5 (Figure 12) and H10a-H5 (Figure 13) and the dihedral angles H2-C2-C3-H3 (Figure 14), H3-C3-C4-H4 (Figure 15), H4a-C4a-C10a-H10a (Figure 16) and H10a-C10a-C5-H5 (Figure 17) were checked during the MD. The values of the distances H2-H4, H4a-H10a, H4a-H5 and H10a-H5 are the same in all compounds; the same can be said for the values of the dihedral angles H4a-C4a-C10a-H10a and H10a-C10a-C5-H5, which result to be diagnostic parameters to detect the molecules under examination. As far as the distances H2-H3 and H3-H4 and the dihedral angles H2-C2-C3-H3 and H3-C3-C4-H4 are concerned, as expected they assume different values according to the fact that the saccharidic entity derives from D-galactose (compounds 13-19) rather than D-glucose (compounds 20-22); however, inside the two sub-populations the 4 parameters result to be identical.

Figure 18 shows A ¹H NMR Spectrum of the compound 26 (0.5 mM) in PBS, pH=7.7, 37°C; B ¹H NMR Spectrum of the mixture containing the Αβ1-42 peptide (50 uM) and the compound 26 (0.5 mM) in PBS, pH=7.7, 37°C; C STD-NMR spectra acquired on the same mixture acquired with a saturation time of 3.0 s, 2304 scanning procedures. The presence of some signals of the molecule 26 in the STD spectrum (Figure 18C) demonstrates the capability of the compound to link the biological target.

The compound 26, synthetized by conjugating covalently the molecule 17 with a derivative of 7-hydroxycumarina, was planned with the purpose of obtaining a fluorescent ligand of Αβ peptides which can be used to detect the presence of amyloid aggregates through the fluorescence spectroscopy. As the structural data related to the linkage of the compounds 13, 15, 16, 17, 18, 19, 20, 21 and 22 to the Αβ oligomers clearly showed that the saccharidic portion was not fundamental for the identification, the functionalization necessary to the conjunction with the fluorophore was introduced in position 1. Among the library molecules one decided to functionalize the compound 17 which, together with the molecules 19, 20 and 22, results to be the ligand with higher affinity. In order to check if such functionalization had altered the property of linking to the Αβ peptides of the molecule 17, we registered a STD spectrum of the mixture containing the Αβ1 -42 peptide (50 uM) and the compound 26 (0.5 mM) in PBS, pH=7.7, 37°C (Figure 18).

Figure 19 shows the fluorescence spectrum of the compound 26. The molecule has the highest fluorescence emission peak at 464 nm when radiated at 340 nm.

Figure 20 shows ¹H NMR spectra of the compound 17 in deuterated PBS, pH 7.5, 25°C at time 0 (A) and after 12 days (B).

The stability of the end compounds 13-22 and 26 was monitored by means of NMR spectroscopy. In particular, for each compound ¹H NMR spectra were acquired at regular interval of each molecule dissolved in PBS deuterated, pH 7.5, and kept at 25°C, by covering a period of about 12 days, during which all ten compounds turned out to be stable. Figure 20 shows by way of example the spectra registered respectively at time 0 (Figure 20A) and after 12 hours (Figure 20B) on the solution containing the molecule 17.

The capability of the compounds according to the invention of inhibiting the aggregation of Αβ1-42 peptide was evaluated with the assay of Thioflavin T (ThT) [H. LeVine, Protein Sci. 2 (1993) 404-410]. The Αβ1-42 peptide, dissolved at a concentration of 1 10 μΜ in PBS (phosphate-buffered saline), pH = 7.5, was incubated for 24 hours at 37°C and under mild stirring in presence or not of a equimolar concentration of each one of the compounds according to the invention. 10 μΙ_ of each sample were then diluted with 1 10 μΙ_ of a solution of ThT (3 μΜ in PBS, pH = 8.9) and the ThT fluorescence was measured with a Varian Cary Eclipse spectrofluorimeter. All compounds gave significant preliminary results. Such results were validated in particular in case of the compound 17 wherein the increase in fluorescence emitted by ThT, which takes place after the linkage thereof to the Αβ aggregates, resulted to be lower (-57%) for the sample wherein the peptide had been co-incubated with the compound 17. This result clearly demonstrates that such molecule acts as inhibitor of the aggregation of the Αβ peptides.

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Claims

1 . Compounds of general formula (I I I)

I I I

wherein

R1 , R2, R4, e R5 can be equal or different and they can be H , alkyl groups (C1 -C5), OH , OAIkyl, N H₂ ;

R3, R6 can be equal or different and they can be H , alkyl groups (C1 -C5)

- X can be -0-, -OH-, -N H₂-, -NHCO-, -S-

- Z can be -(CH₂)n-, -(CH₂CH₂0)n- with (1 <n<5) or absent

- Y can be R3, H , OH, N H₂, N₃, SH, COOH or a fluorophore group, an agent for the passage of the ematoencephalic barrier, a multivalent device

with exclusion of the following compou

The compounds according to claim 1 , general formula (III) belonging to the class formed by (2R,3R,4R,4aS,5R,10aR)-2-(hydroxymethyl)-5-methoxy-

2,3,4,4a,5,10a-hexahydropyran[2,3-b]chromene-3,4-diol,

(2R,3R,4R,4aS,5R,10aR)-7-amino-2-(hydroxymethyl)-5-methoxy-

2,3,4,4a,5,10a-hexahydropyran[2,3-b]chromene-3,4-diol,

(2R,3R,4R,4aS,5R,10aR)-2-(hydroxymethyl)-5-methoxy-2, 3,4,4a, 5, 10a- hexahydropyran[2,3-b]chromene-3,4,7-triol, (2R,3R_!4R_!4aS_!5R,10aR)-2- (hydroxymethyl)-5,7-dimethoxy-2, 3,4,4a, 5, 10a-hexahydropyran[2,3b]chromene- 3,4-diol, (2R,3R,4R,4aS,5R,10aR)-2-(hydroxymethyl)-7-methyl-5-methoxy- 2,3,4,4a,5,10a-hexahydropyran[2,3-b]chromene-3,4-diol

(2R,3R,4R,4aS,5R,10aR)-2-(hydroxymethyl)-5,8-dimethoxy-2,3,4,4a,5,10a- hexahydropyran[2,3-b]chromene-3,4-diol (2R,3R,4R,4aS,5R,10aR)-2- (hydroxymethyl)-8-methyl-5-methoxy-2,3,4,4a,5,10a-hexahydropyran[2,3- b]chromene-3,4-diol, (2R,3S,4R,4aS,5R,10aR)-2-(hydroxymethyl)-7-methyl-5- methoxy-2,3,4,4a,5,10a-hexahydropyran[2,3-b]chromene-3,4-diol,

(2R,3S,4R,4aS,5R,10aR)-2-(hydroxymethyl)-5,8-dimethoxy-2,3,4,4a,5,10a- hexahydropyran[2,3-b]chromene-3,4-diol), (2R,3S,4R,4aS,5R,10aR)-2- (hydroxymethyl)-8-methyl-5-methoxy-2,3,4,4a,5,10a-hexahydropyran[2,3- b]chromene-3,4-diol.

The compounds according to claim 1 wherein X represents -0-, -OH-, -N H₂- o -S-

The compounds according to claiml wherein Z represents -(CH₂)n- with 1 <n<5; or (CH₂CH₂0)n- with 1 <n<5;

The compounds of general formula (I I I) wherein Y represents H , OH, N H_2, N_3, SH , COOH , a fluorophore group, an agent for the passage of the ematoencephalic barrier or a multivalent device.

The compound according to claim 1 with the following formula

containing a fluorophore group.

7. The compounds as claimed in at least one of claims 1 to 6 for use in the treatment of diseases correlated to an aggregation of the Αβ peptides and/or of the Alzheimer disease or other amyloidosis forms.

8. Pharmaceutically compositions containing at least a compound according to claims 1 - 6 together with pharmaceutically tolerable additives.

9. The pharmaceutically compositions according to claim 8 for use in the treatment of the diseases correlated to an aggregation of the Αβ peptides .

10. The pharmaceutically compositions according to claim 8 for use in the treatment of the Alzheimer disease or other amyloidosis forms.

1 1. The compounds according to claim 1 with variable R3=alkyl (C1 -C5) to modulate the pharmacokinetic properties.

12. A process for obtaining the compounds of formula III comprising the following operations

a. stirring at room temperature of a mixture containing a o- hydroxybenzaldehyde in presence of trimethylorthoformate, methylene chloride and triflate scandium catalyst;

b. subsequent cooling at 0° C and slow adding under stirring of a tri-O- benzyl glycal;

c. reaction at room temperature, purification and obtaining of a compound; d. reaction of said compound with a reducing agent;

e. conjugation with a compound chosen from the class formed by fluorophore groups, agents for the passage of the ematoencephalic barrier, multivalent devices.

13. The compounds obtainable by the process of claim 12.

14. The compounds according to claim 13 di formula (I)

wherein

^R1 ,^R2, ^R3,^R4 Η,Η,Η,ΟΗ;

R1 ,^R2, ^R3,^R4 NH₂ Η,Η,ΟΗ

R1 ,^R2, ^R3,^R4 ΟΗ,Η,Η,ΟΗ

^R1 ,^R2, ^R3,^R4 ΟΜΘ,Η,Η,ΟΗ

R1 ,^R2, ^R3,^R4 CH₃ H,H,OH

R1 ,^R2, ^R3,^R4 H, ΟΜΘ,Η,ΟΗ

R1 ,^R2, ^R3,^R4 H,CH₃ H,OH

R1 ,^R2, ^R3,^R4 CH₃ H,OH,H

R1 ,^R2, ^R3,^R4 H, ΟΜΘ,ΟΗ,Η

R1 ,^R2, ^R3.^R4 H,CH₃ ΟΗ,Η

and Y represents a group chosen from the class formed by fluorophores, agents for the passage of the ematoencephalic barrier, multivalent devices.