CN100358582C - Early senile dementia alpha beta starch spot imaging agent - Google Patents

Abstract

The present invention discloses a novel alpha beta-starch plaque imaging agent for presinal dementia, which has the following structure formula: R4-R2-C=N-R1-R3, wherein the R1 and the R2 represent aromatic rings; the R3 is an N-methyl group or an N, or an N-dimethyl group or a methoxyl group, which is positioned on a para position or an ortho position or a meta position of the aromatic ring on one side; the R4 is a group with radioactive nuclein, which is positioned on the para position or the ortho position or the meta position of the aromatic ring on the other side; the positions of the R3 and the R4 can be exchanged. The alpha beta-starch plaque imaging agent is mainly used for raster display for alpha beta-starch plaque of the intravital central nerve, and diagnosis and evaluation for presinal dementia. The affinity constant of the chemical compound of the present invention and alpha beta (1 to 40) aggregation is very high, which can reach n M grade.

Description

Radiolabeled Schiff bases early senile dementia alpha beta starch spot imaging agent

Technical field

The present invention relates to a kind of medical developer that contains radioactive substance, be specially a kind of early senile dementia alpha beta starch spot imaging agent.

Background technology

One of main neuropathological feature of alzheimer disease (being called for short AD) patient is the senile plaque accumulation, its Main Ingredients and Appearance is amyloid-beta (being called for short A β), A β is one of two macromole marks of AD, also is the goldstandard of clinical postmortem or biopsy diagnosis AD.The stain that pathology detect A β has: (Congo Red, CR), thioflavin-T (Thioflavin-T), thioflavin-S, Chrysamine G (CG) and X-34 etc., these reagent have very high affinity at external and A β to Congo red.If use the radioisotope labeling mentioned reagent, and can effectively break through blood brain barrier (be called for short BBB) and enter brain, just can adopt SPECT or PET technology, carry out senile plaque distribution and quantitative in AD patient's brain in body, visual detection, can improve the early diagnostic rate of AD and differentiate accuracy rate, and can to patient AD by stages, be that the therapeutic scheme (as reducing the A β etc. that A β precursor protein generated, suppressed the generation of A β and gathers, removes generation) of target spot and the research of medicine etc. provide effective evaluation methodology at A β.

The advantage of nuclear medicine image is to have the dyeing of unique pathology or biochemical bonded reagent is made developer with radioisotope labeling, helps disease at body, noninvasive specific diagnosis.Directly,, be not easy to penetrate BBB owing to divide subclass big with radioisotope labeling CG class.In recent years reported in literature the improvement labels of several classes to above chemical compound, obtained certain achievement at zoopery, external autography and preliminary clinicing aspect.

The first kind is ¹⁸F-FDDNP, it is that one roughly the same ibuprofen, naproxen chemical constitution are similar, the competition binding site is different from the chemical compound (Agdeppa ED, Neuroscience 117 (2003) 723-730) of Congo red (CG) and thioflavin (Thioflavine T) when combining with the A beta plaque.

FDDNP DDNP structural formula

This chemical compound has been used for the diagnosis of clinical AD, patient's AD at present ¹⁸The F-FDDNP video picture is concentrated and the low metabolism position consistency of FDG, and the normal control group does not have and concentrates.This developer deficiency is that the injection back is slower from the removing in normal brain activity district.

The second class developer is benzothiophene kind and derivant thereof, is very similar compounds of a class and thioflavin-T (Thioflavin-T) chemical constitution, ¹²⁵I or ¹⁸F, ¹¹The BAT compounds and the A β of C labelling have good affinity, wherein ¹¹The Ki=10nM of the BAT of C labelling (Mathis CA, Bioorg ﹠amp; Medic Chemlett, 2002,12:295-298), ¹¹C-6-0H-BAT is at the clinical preliminary identification that obtains.The characteristics of this compounds are that two aromatic rings of connection are First Five-Year Plan unit's heterocycle, wherein have one for two keys (structural formula as follows), by two keys electron cloud on the aromatic ring of both sides are interacted.Remove soon behind such compound injection of positron radionuclide labelling, the video picture of A beta plaque is clear, is suitable for the diagnosis of clinical early stage AD.But the chemical compound normal brain activity of iodine labeling is removed slow, in order to improve from the removing in normal brain activity district, change S into O, become IBOX, though obviously bring up to 0.8nM with the affinity of A β 1-40, the chemical compound of iodine labeling is still removed slow from the normal brain activity district, the 2min/60min ratio is 1 (Zhuang ZP, Nucl Med Biol, 2001,887-894).Change O into N, increase a pair of key simultaneously, become IMPY, though drop to 15nM with combining of A β, but obviously having increased normal brain activity and blood behind the iodine labeling removes, the 2min/60min ratio is 12, increased target this than (Kung MP, 2002, Brain Research, 2002,202-210), its clinical value needs further checking.

Benzothiazoles IBOX class IMPY class

The 3rd class developer is the simplification of second class.Between two aromatic rings, the simplest is directly to be connected into biphenyl, owing to lose the effect of two keys, influence between two aromatic rings and diminish, and A β affinity decline (between 17～100nM).Further modify the key between two phenyl ring, make the increasing that influences each other between the aromatic rings, connect with five-membered ring, and the one-tenth fluorenes (Lee CW, Nucl Med Biol, 2003:573-580).As long as iodine labeling in place, can reach the Ki (0.92nM) higher with A β, but the fluorenes class of iodine labeling is unhappy from the removing of normal brain activity district, and the 2min/60min ratio is 1.57.

Benzene dienes fluorenes class biphenyl class

In order to improve the removing in normal brain activity district, keeping simultaneously with A β has higher affinity, use carbon-carbon double bond between two aromatic rings, influencing each other between the increase aromatic ring, noval chemical compound be the benzene diene (Kung HF, J AmChem Soc, 2001,123:12740-41).Keep higher level with the affinity costant of A β, reach 1.2nM.With ¹¹The benzene diene of C labelling is 3.8 at normal brain activity district 60min/2min ratio, and external autography shows, ¹¹A β has obvious the combination in the benzene dienes of C labelling and the model mouse brain, target this than higher (Ono M, Nucl MedBiol, 2003,30:565).The benzene diene is a class CNS speckle more likely developer.

Summary of the invention

The invention provides a kind of radiolabeled Schiff bases early senile dementia alpha beta starch spot imaging agent, this developer is used for the video picture of the nervus centralis A β-starch speckle of live body, can diagnose and estimate dementia senilis.

The general structure of this radiolabeled Schiff bases early senile dementia alpha beta starch spot imaging agent is as follows:

R4-R2-C＝N-R1-R3

R1 wherein, R2 is expressed as phenyl ring, naphthols or biphenyl; R3 is in the para-position of a side aromatic ring, is N-methyl or N, N-dimethyl or methoxyl group; R4 is in the para-position or an ortho position or a position of opposite side aromatic ring, for-O ¹¹CH ₃,-NH ¹¹CH ₃,- ¹⁸F or- ¹²⁵The I group; R3 and R4 position are interchangeable.

Aforesaid radiolabeled Schiff bases early senile dementia alpha beta starch spot imaging agent, wherein when R3 was methoxyl group, carbon can be radioactive carbon-11 on this group.

The three kinds of chemical compounds belonging to above-mentioned developer and the affinity costant Ki of starch protein A β (1-40) aggregation are measured, measure used A β (1-40) aggregation and ¹²⁵I-TZDM, its measuring method is as follows:

Get A β (1-40) aggregation (final analysis concentration is 10-50nM) of 50 μ L, add 50 μ L's ¹²⁵I-TZDM (100,000 countings/min), add the competitor of 50 μ L, and final volume is diluted to 1mL.Place after 3 hours under the room temperature and separate with cell harvestor, diffusion barrier is a Whatman GF/B filter membrane, and with counting on γ-counter measures film, the Ki result who calculates competitor is as follows:

Compound K i (nM)

2.65

12.7

10.32

This shows that the affinity costant of these three chemical compounds and A β (1-40) aggregation is very high, reaches the nM level, all can become the diagnostic agent and the treatment therapeutic evaluation agent of presenile dementia.

The specific embodiment

Embodiment one ¹¹The synthesizing hydroxyl Schiff bases developer of C labelling

Synthesizing of precursor:

Take by weighing 1.8g to N, the N dimethylbenzaldehyde is dissolved in the 30ml dehydrated alcohol, adds the para-aminophenol of 1.5g again, refluxes 3 hours.A large amount of flaxen precipitations are arranged, and filtration, drying obtain the flaxen crystallization of 2.77g, and productive rate is 89%.H?NMR(500MHZ，DMSO，δ)：3.0(6H)，6.77(4H)，7.10(2H)，7.71(2H)，8.39(1H)，9.3(1H)。

Radioactive label:

Take by weighing 1mg to N, N dimethyl, to hydroxyl Schiff alkali is dissolved among the 0.4mlDMSO, adds 2N NaOH 10 μ L.In this solution, feed ¹¹CH ₃I separates with partly preparing HPLC, and detached dowel is the C-18 post, and mobile phase is water: acetonitrile (710: 290 V/V), flow velocity 1mL/min, wavelength 280nm.The Rt of product is 5.5min, collects the product peak.Or, in label, add 10ml water with the separation of Sep-Pak C-18 post, and cross the C-18 post, the water flushing washes product get off with 1ml ethanol.Labeling effciency is 73%.

Embodiment two ¹¹Hydroxyl Schiff bases developer is synthetic between the C labelling

Synthesizing of precursor:

Take by weighing 1.8g to N, the N dimethylbenzaldehyde is dissolved in the 30ml dehydrated alcohol, adds the 3-amino-phenol of 1.5g again, refluxes 3 hours.A large amount of flaxen precipitations are arranged, and filtration, drying obtain the flaxen crystallization of 2.5g, and productive rate is 81%.H?NMR(500MHZ，DMSO，δ)：3.0(6H)，5.06(1H)，6.62(2H)，6.7(2H)，6.8(1H)，7.10(1H)，7.44(2H)，8.9(1H)。

Radioactive label:

Take by weighing 1mg to N, N dimethyl, a hydroxyl Schiff alkali are dissolved among the 0.4mlDMSO, add 2N NaOH 10 μ L.In this solution, feed ¹¹CH ₃I separates with partly preparing HPLC, and detached dowel is the C-18 post, and mobile phase is water: acetonitrile (710: 290 V/V), flow velocity 1mL/min, wavelength 280nm.The Rt of product is 5.5min, collects the product peak.Or, in label, add 10ml water with the separation of Sep-Pak C-18 post, and cross the C-18 post, the water flushing washes product get off with 1ml ethanol.Labeling effciency is 70%.

Embodiment three ¹¹Synthesizing of the naphthols Schiff bases developer of C labelling

Synthesizing of precursor:

Take by weighing 1.8g to N, the N dimethylbenzaldehyde is dissolved in the 30ml dehydrated alcohol, adds 5-amino-1-naphthols of 2.15g again, refluxes 3 hours.A large amount of brown precipitations are arranged, filtration, drying, the crystallization that the 1.7g that obtains is brown, productive rate is 50%.H?NMR(500MHZ，DMSO，δ)：3.0(6H)，5.06(1H)，6.6(3H)，7.2(1H)，7.3(2H)，7.4(3H)，8.1(H)，9.1(1H)。

Radioactive label:

Take by weighing 1mg to N, N dimethyl, naphthols Schiff alkali are dissolved among the 0.4mlDMSO, add 2NNaOH 10 μ L.In this solution, feed ¹¹CH ₃I separates with partly preparing HPLC, and detached dowel is the C-18 post, and mobile phase is water: acetonitrile (710: 290 V/V), flow velocity 1mL/min, wavelength 280nm.The Rt of product is 5.5min, collects the product peak.Or, in label, add 10ml water with the separation of Sep-Pak C-18 post, and cross the C-18 post, the water flushing washes product get off with 1ml ethanol.Labeling effciency is 75%.

Embodiment four ¹¹Synthesizing of the biphenyl Schiff bases developer of C labelling

Synthesizing of precursor:

Take by weighing 1.8g to N, the N dimethylbenzaldehyde is dissolved in the 30ml dehydrated alcohol, adds 2-amido-4-benzene-phenol of 2.47g again, refluxes 3 hours.The precipitation that a large amount of whites are arranged, filtration, drying, the crystallization of the 1.37g white that obtains, productive rate is 36%.HNMR(500MHZ，DMSO，δ)：3.0(6H)，5.06(1H)，6.62(2H)，6.8(H)，7.22(1H)，7.3(2H)，7.32(2H)，7.44(2H)，7.48(2H)，8.8(1H)。

Radioactive label:

Take by weighing 1mg to N, N dimethyl diphenyl Schiff alkali is dissolved among the 0.4mlDMSO, adds 2N NaOH10 μ L.In this solution, feed ¹¹CH ₃I separates with partly preparing HPLC, and detached dowel is the C-18 post, and mobile phase is water: acetonitrile (710: 290 V/V), flow velocity 1mL/min, wavelength 280nm.The Rt of product is 5.5min, collects the product peak.Or, in label, add 10ml water with the separation of Sep-Pak C-18 post, and cross the C-18 post, the water flushing washes product get off with 1ml ethanol.Labeling effciency is 23%.

Embodiment five ¹¹Synthetic (the N-C place-exchange) to hydroxyl Schiff bases developer of C labelling

Synthesizing of precursor:

Take by weighing 1.2g to N, the N dimethylaniline is dissolved in the 30ml dehydrated alcohol, adds the para-aminophenol of 1.2g again, refluxes 3 hours.A large amount of flaxen precipitations are arranged, and filtration, drying obtain the flaxen crystallization of 2.1g, and productive rate is 87%.H?NMR(500MHZ，DMSO，δ)：3.0(6H)，5.0(H)，6.60(2H)，6.76(2H)，7.10(2H)，7.52(2H)，9.2(1H)。

Radioactive label:

Take by weighing 1mg to N, N dimethyl, to hydroxyl Schiff alkali is dissolved among the 0.4mlDMSO, adds 2N NaOH 10 μ L.In this solution, feed ¹¹CH ₃I separates with partly preparing HPLC, and detached dowel is the C-18 post, and mobile phase is water: acetonitrile (710: 290 V/V), flow velocity 1mL/min, wavelength 280nm.The Rt of product is 5.5min, collects the product peak.Or, in label, add 10ml water with the separation of Sep-Pak C-18 post, and cross the C-18 post, the water flushing washes product get off with 1ml ethanol.Labeling effciency is 75%.

Embodiment six ¹¹The synthesizing amido Schiff bases developer of C labelling

Synthesizing of precursor:

Take by weighing the p-phenylenediamine (PPD) of 1.0g, be dissolved in the 15ml dehydrated alcohol, reflux.Slowly drip the N to 1.2g in solution, N dimethylbenzaldehyde (alcoholic solution) adds in 90min, refluxes 2 hours again.A large amount of xanchromatic precipitations are arranged, and filtration, drying obtain the flaxen thick product of 0.6g.Separate with lamellae, ethyl acetate and normal hexane are made mobile phase, obtain the 0.5g product.H?NMR(500MHZ，DMSO，δ)：3.0(6H)，4.2(2H)，6.5(2H)，6.77(2H)，7.2(2H)，7.44(2H)，9.3(1H)。

Radioactive label:

Take by weighing 1mg to N, N dimethyl, to amido Schiff alkali is dissolved among the 0.4mlDMSO, adds 2N NaOH 10 μ L.In this solution, feed ¹¹CH ₃I separates with partly preparing HPLC, and detached dowel is the C-18 post, and mobile phase is water: and acetonitrile (71O: 290V/V), flow velocity 1mL/min, wavelength 280nm.The Rt of product is 5.5min, collects the product peak.Or, in label, add 10ml water with the separation of Sep-Pak C-18 post, and cross the C-18 post, the water flushing washes product get off with 1ml ethanol.Labeling effciency is 61%.

Embodiment seven ¹¹The methoxyl group of C labelling is to synthesizing of amido Schiff bases developer

Synthesizing of precursor:

Take by weighing the p-phenylenediamine (PPD) of 1.0g, be dissolved in the 15ml dehydrated alcohol, reflux.In solution, slowly drip P-methoxybenzal-dehyde (alcoholic solution), in 90min, add, refluxed again 2 hours 1.1g.Xanchromatic precipitation is arranged, and filtration, drying obtain the xanchromatic thick product of 0.5g.Separate with lamellae, ethyl acetate and normal hexane are made mobile phase, obtain the 0.45g product.H?NMR(500MHZ，DMSO，δ)：3.7(3H)，4.0(2H)，6.5(2H)，6.80(2H)，7.0(2H)，7.51(2H)，9.3(1H)。

Radioactive label:

The methoxyl group that takes by weighing 1mg is dissolved among the 0.4mlDMSO amido Schiff alkali, adds 2N NaOH10 μ L.In this solution, feed ¹¹CH ₃I separates with partly preparing HPLC, and detached dowel is the C-18 post, and mobile phase is water: acetonitrile (710: 290 V/V), flow velocity 1mL/min, wavelength 280nm.The Rt of product is 5.5min, collects the product peak.Or, in label, add 10ml water with the separation of Sep-Pak C-18 post, and cross the C-18 post, the water flushing washes product get off with 1ml ethanol.Labeling effciency is 58%.

Carbon on this developer methoxyl group can be radioactive carbon-11, is used for video picture simultaneously.

Embodiment eight ¹⁸Synthesizing of the para-position Schiff bases developer of F labelling

Synthesizing of precursor:

Take by weighing 1.19g to N, the N dimethylbenzaldehyde is dissolved in the 30ml dehydrated alcohol, adds the paranitroanilinum of 1.1g again, refluxes 3 hours.A large amount of flaxen precipitations are arranged, filtration, drying, ethyl alcohol recrystallization obtains the 1.35g product, and productive rate is 65%.H?NMR(500MHZ，DMSO，δ)：3.05(6H)，6.60(2H)，6.80(2H)，7.69(2H)，7.95(2H)，9.67(1H)。

Radioactive label:

Accelerator-produced ¹⁸F ^-Ion after QMA absorption by the K2.2.2/K of 1.5ml ₂CO ₃The acetonitrile solution eluting is gone into reaction tube, the DMSO solution that after secondary removes acetonitrile, adds the nitro precursor that contains 2mg-3mg, behind reaction 10min under 130 ℃, cooling is after adding 10ml water and residue are mixed, and the startup negative pressure enters waste liquid bottle with liquid in the reaction bulb through the C-18 post.Thick product is attracted on the C-18 post.Divide three times 15ml water to be sucked waste liquid bottle through negative pressure, with K2.2.2 and the DMSO eluting that remains on the C-18.Again threeway is switched to the product receiving flask, add 1ml ethanol receiving flask is gone in the product drip washing on the C-18 post.Add an amount of normal saline,, obtain after aseptic filter membrane ¹⁸F-N, N dimethyl, to fluorine Schiff alkali.Mark rate is 25%.

Embodiment nine ¹⁸Synthesizing of the ortho position Schiff bases developer of F labelling

Synthesizing of precursor:

Take by weighing 1.19g to N, the N dimethylbenzaldehyde is dissolved in the 30ml dehydrated alcohol, adds the ortho-nitraniline of 1.1g again, refluxes 3 hours.A large amount of flaxen precipitations are arranged, filtration, drying, ethyl alcohol recrystallization obtains the 1.12g product, and productive rate is 42%.H?NMR(500MHZ，DMSO，δ)：3.0(6H)，6.62(2H)，7.44(2H)，7.52(2H)，7.7(2H)，8.21(H)，8.39(1H)。

Radioactive label:

Accelerator-produced ¹⁸F ^-Ion after QMA absorption by the K2.2.2/K of 1.5ml ₂CO ₃The acetonitrile solution eluting is gone into reaction tube, after secondary removes acetonitrile, add contain 2mg-3mg between the DMSO solution of nitro precursor, behind reaction 10min under 130 ℃, cooling is after adding 10ml water and residue are mixed, and the startup negative pressure enters waste liquid bottle with liquid in the reaction bulb through the C-18 post.Thick product is attracted on the C-18 post.Divide three times 15ml water to be sucked waste liquid bottle through negative pressure, with K2.2.2 and the DMSO eluting that remains on the C-18.Again threeway is switched to the product receiving flask, add 1ml ethanol receiving flask is gone in the product drip washing on the C-18 post.Add an amount of normal saline,, obtain after aseptic filter membrane ¹⁸F-N, N dimethyl, adjacent fluorine Schiff alkali.Mark rate is 18%.

Embodiment ten ¹²⁵Synthesizing of the Schiff bases developer of I labelling

Synthesizing of precursor:

Take by weighing 298mg to N, the N dimethylbenzaldehyde is dissolved in the 30ml dehydrated alcohol, adds the para-bromoaniline of 344mg again, refluxes 3 hours.Remove ethanol, filtration, drying, ethyl alcohol recrystallization obtains the 0.4g product, productive rate 65%.Fusing point: 136 ℃, H NMR (500MHZ, DMSO, δ): 2.92 (6H), 6.41 (2H), 7.05 (2H), 7.6 (2H), 9.57 (H).

Get 52mg to bromine Schiff alkali, with the Pd (Ph of 20mg ₃P) ₄Be dissolved in the 12ml triethylamine solution, 90 ℃ of reactions 12 hours.Desolventize,, obtain the precursor of 20mg with TLC method purification.

Radioactive label:

Prepare the Xi Dingji precursor alcoholic solution of 50 μ g/50 μ L, add an amount of Na ¹²⁵I solution is regulated PH, and room temperature is reaction 10min down, adds the NaHSO of 100 μ L ₄Neutralization.Directly use ethyl acetate extraction, dry up, the dissolving of 10% ethanol normal saline solution.

Claims (2)

1. radiolabeled Schiff bases early senile dementia alpha beta starch spot imaging agent, its general structure is as follows:

R4-R2-C＝N-R1-R3

R1 wherein, R2 is expressed as phenyl ring, naphthols or biphenyl; R3 is in the para-position of a side aromatic ring, is N-methyl or N, N-dimethyl or methoxyl group; R4 is in the para-position or an ortho position or a position of opposite side aromatic ring, for-O ¹¹CH ₃,-NH ¹¹CH ₃,- ¹⁸F or- ¹²⁵The I group; R3 and R4 position are interchangeable.

2. radiolabeled Schiff bases early senile dementia alpha beta starch spot imaging agent as claimed in claim 1, it is characterized in that: when R3 was methoxyl group, carbon can be radioactive carbon-11 on this group.