ABSTRACT
BACKGROUND AND PURPOSE: Drugs with anticholinergic properties might have a negative impact on cognition, but findings are still conflicting. The association was evaluated between anticholinergic drugs and cognitive performance in primary care patients with first cognitive complaints. METHODS: From April 2013 to March 2014, 353 general practitioners administered the Mini-Mental State Examination (MMSE) to patients presenting with first cognitive complaints. Drug history was collected and the anticholinergic cognitive burden (ACB) was scored and categorized as ACB 0, ACB 1 and ACB 2+. A mixed effect linear regression model was used to assess the association between ACB and MMSE score. RESULTS: Of 4249 subjects entering the study (mean age 77 ± 8.2 years, 66.4% women and mean years of schooling 8.9 ± 4.5), 25.8% received at least one drug with anticholinergic action. According to multivariate analysis, and after adjustment for several confounders, subjects with ACB 2+ had a statistically significant lower MMSE score compared with those with ACB 0 (ß -0.63; 95% confidence interval -1.19; -0.07). Subjects with ACB 1 had a non-statistically significant lower MMSE score than those with ACB 0 (ß -0.11; 95% confidence interval -0.37; 0.15). CONCLUSIONS: Anticholinergic medication might affect cognitive function in people with first cognitive complaints. Alternatives should be taken into account when possible, balancing the benefits and harms of these medications.
Subject(s)
Cholinergic Antagonists/adverse effects , Cognition Disorders/chemically induced , Aged , Aged, 80 and over , Body Burden , Cholinergic Antagonists/therapeutic use , Cognition Disorders/epidemiology , Cognition Disorders/psychology , Educational Status , Female , Humans , Male , Neuropsychological Tests , Primary Health Care , Psychomotor Performance , Socioeconomic Factors , Treatment OutcomeABSTRACT
BACKGROUND: Subjects with severe cognitive impairment (CI) have a high-risk of hip fractures with increased rate of adverse postoperative functional outcomes and mortality. AIM: To evaluate the impact of different degrees of CI on functional recovery and mortality after hip fracture. DESIGN: Prospective observational study. SETTING: Two orthopedic surgery units. POPULATION: Two hundred twenty-eight consecutive patients after a hip surgery. METHODS: Patients were assessed at baseline through the Short Portable Mental Status Questionnaire (SPMSQ), an instrument that allows to categorize subjects as follows: cognitively intact (SPMSQ≥8) or with mild (SPMSQ=6-7), moderate (SPMSQ=3-5) and severe CI (SPMSQ<3). Barthel Index (BI) was used to assess functional disability. All patients underwent rehabilitation from the day after surgery to discharge (mean length of stay =10.2±3.4). Outcome measures were: (1) overall mortality up to 12 months after surgery; (2) motor ability achieved at discharge from the orthopedic ward (sitting, standing, walking); (3) BI and SPMSQ at 1, 3, 6 and 12 months postoperatively. RESULTS: All degrees of severity of CI were inversely correlated to the ability to walk at hospital discharge. At one year from surgery, the majority of patients with CI were functionally severely dependent, whereas about half of the cognitively intact ones gained a functional independence status. CI and the level of premorbid disability influenced the risk of death. CONCLUSION: CI for all degrees of severity is a negative prognostic factor in elderly patients with hip fracture. CLINICAL REHABILITATION IMPACT: We suggest evaluating the cognitive status of patients with hip fracture as it affects both the short and long-term functional recovery at any degree of severity.
Subject(s)
Cognition Disorders/complications , Hip Fractures/rehabilitation , Hip Fractures/surgery , Physical Therapy Modalities , Aged, 80 and over , Disability Evaluation , Female , Hip Fractures/mortality , Humans , Length of Stay/statistics & numerical data , Male , Mental Status Schedule , Prognosis , Prospective Studies , Risk Factors , Surveys and QuestionnairesABSTRACT
BACKGROUND: In the field of rehabilitation it is crucial to define if changes in functional scores correspond to relevant clinical improvements. AIM: To assess whether cognition affects motor recovery in post-stroke patients using a clinical meaningful criterion: the minimal clinically important difference (MCID). DESIGN: Retrospective cohort study. SETTING: Inpatient rehabilitation clinic POPULATION: Two hundred nine first-ever stroke patients undergoing a post-acute inpatient rehabilitation. METHODS: Cognitive status was assessed with the cognitive FIM and the Mini-Mental State Examination (MMSE). The response to the rehabilitation was defined as the achievement of the MCID between admission and discharge in the motor FIM (responder) and both in the motor and in the cognitive FIM (best-responder). RESULTS: Subjects with a baseline higher MMSE>24.9 had a near four-fold higher probability of being responder (OR 3.91; 95% CI 1.72-8.89) and a two-fold higher probability of being best-responder (OR 2.69; 95% CI 1.24-5.84) on motor FIM as compared to those with a MMSE≤24.9. A duration of the rehabilitation of 55-61 days implies a three-fold higher probability (OR 3.17; 95% CI 1.15-8.72) to be responder as compared to shorter period of treatment; a treatment >61 days does not involve a greater probability of response. CONCLUSIONS: This is the first study that examined post-stroke motor recovery mainly in terms of clinical relevance (MCID). Subjects with a higher cognitive level are more likely to achieve a clinically meaningful recovery. CLINICAL REHABILITATION IMPACT: MCID can be applied extensively to post-stroke patients undergoing to an inpatient rehabilitation in order to have a clinically useful instrument that assess the recovery.
Subject(s)
Cognition/physiology , Stroke Rehabilitation , Stroke/physiopathology , Activities of Daily Living , Aged , Aged, 80 and over , Disability Evaluation , Female , Health Status Indicators , Humans , Italy , Male , Motor Activity/physiology , Physical Therapy Modalities , Prognosis , Recovery of Function , Rehabilitation Centers , Retrospective Studies , Risk Factors , Treatment OutcomeABSTRACT
The present article attempts to provide, on the basis of data emerging from studies carried out in our laboratories, a summary of the chemical and pharmacological properties of the new compound N-[(4-trifluoromethyl)benzyl]4- methoxybutyramide (GET73). Particular emphasis is given to findings obtained in vivo and in vitro suggesting that an allosteric modulation of metabotropic glutamate receptor 5 (mGlu5 receptor) by GET73 may represent the mechanism underlying the effects of the compound produced on rat hippocampal glutamate and GABA transmission. Furthermore, behavioural findings demonstrating how this new compound reduces alcohol intake, displays anxiolytic properties, and influences spatial memory in rats are also summarized. Since mGlu5 receptors play an important role in regulating several central actions of drugs of abuse, and the hippocampus is a crucial brain area involved in addiction, anxiety, and spatial memory, a possible link between mGlu5 receptor allosteric modulation and the profiles of action of GET73 is proposed, although to date no studies have yet explored GET73 binding at the mGlu5 receptor orthosteric and/or allosteric sites. Following a brief overview of glutamatergic neurotransmission, mGlu receptor structures and activation mechanisms, the general properties of mGlu5 receptor and its allosteric modulators are described in the first part of the review.
Subject(s)
Anilides/pharmacology , Hippocampus/metabolism , Receptor, Metabotropic Glutamate 5/metabolism , Synaptic Transmission/drug effects , Alcohol Drinking , Allosteric Regulation , Anilides/chemical synthesis , Anilides/chemistry , Animals , Anti-Anxiety Agents/chemical synthesis , Anti-Anxiety Agents/chemistry , Anti-Anxiety Agents/pharmacology , Hippocampus/drug effects , Receptor, Metabotropic Glutamate 5/chemistry , Receptors, N-Methyl-D-Aspartate/metabolismABSTRACT
The presence of episodic memory impairment is required for the diagnosis of Alzheimer's dementia by all current diagnostic criteria. The new research criteria proposed by Dubois et al. (Lancet Neurol 6:734-746, 2007) require that the impairment should not improve significantly with cueing, recognition testing nor after the control of effective encoding. This is considered to be the core deficit of "prodromal Alzheimer's disease". The Free and Cued Selective Reminding Test (FCSRT) is a memory test that allows in assessing these specific features of memory impairment. Here, we report normative data for an Italian version of the FCSRT. The test is based on the 12 pictorial stimuli, 6 belonging to the living domain, and 6 to the non-living domain. Six scores were derived from the performance of 227 healthy Italian adults, with age, sex and education homogenously distributed across subgroups: immediate free recall (IFR), immediate total recall (ITR), delayed-free recall (DFR), delayed total recall (DTR), Index of Sensitivity of Cueing (ISC), number of intrusions. In multiple regression analyses, age emerged as an influencing factor for both IFR and DFR, with older people obtaining lower scores. Education and gender appear to influence only IFR, with better performance by more educated subjects and females. Adjusted scores were used to determine inferential cutoff scores and to compute equivalent scores.
Subject(s)
Cues , Memory/physiology , Neuropsychological Tests , Adult , Age Factors , Aged , Aged, 80 and over , Female , Humans , Italy , Male , Middle Aged , Predictive Value of Tests , Reaction Time , Reference Values , Regression Analysis , Sex FactorsABSTRACT
AIM: The aim of this study was to assess whether 18F-fluorodeoxyglucose positron emission tomography differentiates amnestic (aMCI) from single-non-amnestic mild cognitive impairment (snaMCI) with executive dysfunction. METHODS: Sixteen aMCI subjects (62% females, age 75+/-8 years) and 14 snaMCI subjects (71% females, age 74+/-6 years) underwent [18F]FDG-PET and clinical follow-up. Comparisons between MCI subgroups and with seven cognitively normal elderly subjects were performed using SPM2. RESULTS: At baseline aMCI and snaMCI exhibited a similar pattern of hypometabolism, mostly in the posterior cingulate gyrus, as compared with controls. In the comparison between the MCI subtypes, the aMCI subjects showed reduced metabolism in the medial temporal lobes (MTL) (hippocampus, fusiform gyrus and amygdala). At follow-up 12 aMCI developed Alzheimer's disease (AD), while snaMCI had a heterogeneous course, including five subjects who developed Lewy body dementia. CONCLUSIONS: The patterns of altered brain metabolism in aMCI and snaMCI subjects compared to controls are similar and do not provide evidence for making clinical distinctions between them. Comparison between the two MCI subtypes showed MTL hypometabolism in aMCI subjects, possibly reflecting the fact that most had prodromal AD.
Subject(s)
Amnesia/pathology , Cognition Disorders/pathology , Fluorodeoxyglucose F18/pharmacology , Hippocampus/metabolism , Positron-Emission Tomography/methods , Aged , Amnesia/diagnosis , Automation , Cognition Disorders/diagnosis , Female , Glucose/metabolism , Hippocampus/pathology , Humans , Lewy Body Disease/pathology , Male , Middle Aged , Neuropsychological Tests , Temporal Lobe/pathologyABSTRACT
BACKGROUND AND PURPOSE: Frontotemporal lobar degeneration (FTLD) is considered as a proteinopathy; therefore, it is conceivable that genes encoding for factors involved in protein misfolding and/or degradation could play a role in its pathogenesis. METHODS: An association study of defective in cullin neddylation 1 (DCN-1)-domain containing 1 (DCUN1D1), which is involved in protein degradation, was carried out in a population of 220 patients with FTLD as compared with 229 age-matched controls. RESULTS: A statistically significant increased frequency of the GG genotype of the DCUN1D1 rs4859146 single nucleotide polymorphism (SNP) was observed in patients compared with controls (6.9 vs. 1.7%, P = 0.011, adjusted OR: 4.39, 95% CI: 1.40-13.78). Stratifying according to the clinical syndrome, significant differences were observed between the behavioral variant of frontotemporal dementia and controls (GG frequency: 6.3 vs. 1.7%, P = 0.02, OR:4.0, 95%, CI = 1.24-12.92), as well as between patients with progressive aphasia compared with controls (15.4 vs. 1.7%, P = 0.014, OR = 11.30, 95%, CI = 1.63-78.45), but not in patients with SD versus controls (8.3 vs. 1.7%, P = 0.18, OR = 5.24, 95% C.I. = 0.45-60.63). No significant differences in allelic and genotypic frequencies of the DCUN1D1 rs4859147 SNP were found. CONCLUSIONS: The GG genotype of the DCUN1D1 rs4859147 SNP represents a risk factor for the development of FTLD, increasing the risk of about fourfold.
Subject(s)
Dementia/etiology , Dementia/genetics , Genetic Predisposition to Disease , Oncogene Proteins/genetics , Polymorphism, Single Nucleotide/genetics , Aged , DNA Mutational Analysis/methods , Exons/genetics , Female , Gene Frequency , Genotype , Humans , Intracellular Signaling Peptides and Proteins , Logistic Models , Male , Middle Aged , Proteins , Proto-Oncogene Proteins , Risk FactorsABSTRACT
BACKGROUND AND AIMS: Neuronal nitric oxide synthase (NOS)1 C276T polymorphism was shown to increase the risk for frontotemporal lobar degeneration (FTLD). In the brain, both NOS1 and NOS3 (endothelial isoform) have been detected. The distribution of NOS3 G894T (Glu298Asp) and T-786C single nucleotide polymorphisms (SNPs) was analyzed in a population of 222 patients with FTLD compared with 218 age-matched controls to determine whether they could influence the susceptibility to develop the disease. RESULTS: A statistically significant increased frequency of the NOS3 G894T SNP was observed in patients as compared with controls (40.0 vs. 31.4%, P = 0.011, OR: 1.65, CI: 1.13-2.42). Conversely, the distribution of the T-786C SNP was similar in patients and controls. No differences were observed stratifying according to gender. DISCUSSION: The NOS3 G894T polymorphism likely acts as risk factor for sporadic FTLD, but studies in larger populations are needed to confirm these preliminary findings.
Subject(s)
Frontotemporal Lobar Degeneration/enzymology , Frontotemporal Lobar Degeneration/genetics , Genetic Predisposition to Disease/genetics , Nitric Oxide Synthase Type III/genetics , Polymorphism, Single Nucleotide/genetics , Aged , Case-Control Studies , DNA Mutational Analysis , Female , Frontotemporal Lobar Degeneration/epidemiology , Genetic Predisposition to Disease/epidemiology , Genetic Testing/methods , Humans , Male , Middle Aged , Nitric Oxide Synthase Type III/deficiency , Pregnancy , Risk FactorsABSTRACT
Genetic Creutzfeldt-Jakob disease (gCJD) is caused by a range of mutations in the prion protein gene (PRNP). We describe the first Italian case of gCJD associated with the rare PRNP E196K mutation. The disease showed an atypical presentation featuring dementia without motor signs in a 75-year-old woman. The case lacked both a known family history of a similar neurological disease and the typical EEG pattern; it was misdiagnosed as frontotemporal dementia. The present case emphasizes that vigilance must be kept high to avoid missing gCJD cases falling outside a typical phenotypical presentation and a known family history, especially in the elderly, in whom an alternative, more common, but incorrect diagnosis may be made.
Subject(s)
Creutzfeldt-Jakob Syndrome/genetics , Glutamic Acid/genetics , Lysine/genetics , Prions/genetics , Aged , Creutzfeldt-Jakob Syndrome/pathology , DNA Mutational Analysis/methods , Female , Humans , Italy , Magnetic Resonance Imaging , Prion ProteinsABSTRACT
BACKGROUND AND PURPOSE: Progranulin (PGRN) expression is increased in activated microglia in Alzheimer's disease (AD) brain, suggesting a potential role in this pathology. METHODS: A mutation scanning of exons and flanking regions of PGRN was carried out in 120 patients with sporadic frontotemporal lobar degeneration and 145 with sporadic AD. RESULTS: Amongst variants not yet deposited, a novel allelic variant was identified in Exon 1 (g100169G > A). It leads to an amino acidic change (p.Gly35Arg) and was observed in a patient with late onset AD. In silico analysis predicted that this mutation is possibly damaging. A second variant (g.100165C > T), resulting in a silent mutation (pAsp33Asp), was found in a patient with semantic dementia and in another with early onset AD. Both variants were absent in 226 controls. In addition, two rare non-pathogenic variants lying very close to PGRN splice-site regions (IVS2 + 7-->G > A and IVS7 + 7-->G > A) were observed. Transcriptional analysis in peripheral blood mononuclear cells from patients demonstrated they do not affect exon splicing. CONCLUSIONS: A novel putative PGRN mutation leading to an amino acidic substitution was identified in a patient with clinical AD.
Subject(s)
Alzheimer Disease/genetics , Dementia/genetics , Exons/genetics , Intercellular Signaling Peptides and Proteins/genetics , Age of Onset , Aged , Aged, 80 and over , Alzheimer Disease/epidemiology , Amino Acid Substitution , Case-Control Studies , DNA Mutational Analysis , Dementia/epidemiology , Female , Humans , Intercellular Signaling Peptides and Proteins/physiology , Male , Middle Aged , Polymorphism, Single Nucleotide , Progranulins , RNA Splicing , Sequence Analysis, DNA , Structure-Activity Relationship , Transcription, GeneticABSTRACT
The neuronal nitric oxide synthase (nNOS) is abundantly expressed in the brain and its transcripts have been found in the frontal cerebral cortex. Eighty-nine patients with different neurodegenerative tau-related disorders, including 71 patients with frontotemporal lobar degeneration (FTLD), 12 with progressive supranuclear palsy (PSP) and 6 with corticobasal degeneration (CBD), were genotyped for the C276T single nucleotide polymorphism (SNP) in exon 29 of the nNOS gene and compared with 190 age-matched controls (CON). A significantly increased allelic frequency of the T allele was observed in patients compared with CON (40.4% vs. 29.7%, P = 0.014, OR: 1.94, CI: 1.15-3.27). Considering each disorder separately, significance was reached for FTLD only (39.4%, P = 0.0248 versus controls, OR: 1.96, CI: 1.11-3.47). However, the frequency of the T allele was elevated also in patients with PSP (45.8%) and CBD (41.7%). No differences were observed stratifying according to gender or apolipoprotein E status. The C276T SNP acts as risk factor for sporadic FTLD, possibly influencing NOS1 transcription. Studies in larger populations are needed to confirm its role in PSP and CBD.
Subject(s)
Brain/enzymology , Dementia/enzymology , Dementia/genetics , Genetic Predisposition to Disease/genetics , Nitric Oxide Synthase Type I/genetics , Polymorphism, Genetic/genetics , Aged , Brain/physiopathology , DNA Mutational Analysis , Dementia/physiopathology , Female , Gene Expression Regulation, Enzymologic/genetics , Gene Frequency/genetics , Genetic Markers/genetics , Genetic Testing , Genotype , Humans , Male , Middle Aged , Neurons/enzymology , Risk FactorsABSTRACT
We describe a patient with probable dementia with Lewy bodies (DLB) whose Parkinsonism worsened after administration of rivastigmine within the therapeutic dose range. Some extrapyramidal signs (EPS) then reversed to pre-treatment level after rivastigmine dose reduction. We draw attention to the need of EPS monitoring during titration of cholinesterase inhibitors in patients with DLB. This is the first report to our knowledge of iatrogenic worsening of Parkinsonism which was successfully managed by dose reduction.
Subject(s)
Acetylcholine/metabolism , Cholinesterase Inhibitors/administration & dosage , Parkinsonian Disorders/drug therapy , Phenylcarbamates/administration & dosage , Aged , Cholinesterase Inhibitors/adverse effects , Disease Progression , Humans , Lewy Body Disease/complications , Male , Parkinsonian Disorders/etiology , Phenylcarbamates/adverse effects , Rivastigmine , Time FactorsABSTRACT
Epidemiological data show a higher prevalence of late-onset Alzheimer's disease (AD) in women. The estrogenic deficiency in the post-menopausal period is suspected to be the cause of the gender-related risk of the disease, but studies on the estrogenic therapy and occurrence of AD were not consistent and sometimes contradicting. The aim of this study is to investigate whether a higher exposure to endogenous estrogens is associated with lower risk of dementia or not. Two hundred and four AD patients and 201 control women were considered. By interviews, we evaluated different variables, indirectly correlated to estrogenic natural exposure, as well as educational level and head trauma. These data were correlated in the AD group with the disease progression, as well as with the age at onset. Unexpectedly, we found a significant higher number of pregnancies in the AD than in the control group. Within the AD cases, the number of lifetime pregnancies is related to an earlier onset of the disease. As previously reported, we confirmed that the educational level is a protective factor and that major head trauma represents a risk factor in developing AD. The higher number of pregnancies and a less frequency of nulliparous women, indirectly relate the AD group to a higher estro-progestinic exposure. These findings suggest that it is the increase of progesterone or estrogens level--and not the estrogens decrease, as previously indicated by other authors--that could play a role in the Alzheimer's pathology.
Subject(s)
Alzheimer Disease/epidemiology , Parity/physiology , Aged , Aged, 80 and over , Alzheimer Disease/prevention & control , Cognition Disorders/epidemiology , Cognition Disorders/prevention & control , Estrogen Replacement Therapy , Female , Humans , Incidence , Pregnancy , Retrospective Studies , Risk Factors , United States/epidemiologyABSTRACT
5-Sulfanyl-3-alkylaminoisothiazole dioxide derivatives have been identified as a new class of potent inhibitors of rat aortic myocite proliferation. They were prepared by applying a simple methodology able to introduce a heteroatom on C-5 of the 3-alkylaminoisothiazole dioxide system. 3-Aminosubstituted-5-chloroisothiazole dioxides react smoothly not only with S-nucleophiles but also with N- and O-nucleophiles affording the corresponding 5-heterosubstituted isothiazole dioxides through an addition-elimination reaction. The behavior of 3-alkylamino-4-bromo-isothiazole 1,1-dioxide with S-, N- and O-nucleophiles affording the same products has also been described. On the contrary, the 3-amino-4,5-unsubstituted isothiazole dioxide system reacts easily only with sulfur nucleophiles affording the corresponding 4,5-dihydro-5-sulfanylderivatives through a simple Michael addition reaction.
Subject(s)
Oxygen/chemistry , Sulfur/chemistry , Thiazoles/chemistry , Thiazoles/chemical synthesis , Alkyl and Aryl Transferases/antagonists & inhibitors , Alkyl and Aryl Transferases/metabolism , Alkylation , Amination , Animals , Cell Proliferation/drug effects , Cells, Cultured , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Male , Molecular Structure , Myocytes, Smooth Muscle/cytology , Myocytes, Smooth Muscle/drug effects , Rats , Rats, Sprague-Dawley , Structure-Activity Relationship , Thiazoles/pharmacologyABSTRACT
Description of a case of probable dementia with Lewy bodies featuring parkinsonism, dementia and supranuclear gaze palsy. This is the first patient to our knowledge affected with vertical gaze palsy receiving clinical diagnosis of DLB when alive and to be treated with cholinesterase inhibitors.
Subject(s)
Lewy Body Disease/pathology , Supranuclear Palsy, Progressive/pathology , Aged , Diagnosis, Differential , Frontal Lobe/diagnostic imaging , Humans , Lewy Body Disease/complications , Lewy Body Disease/diagnostic imaging , Male , Neuropsychological Tests , Positron-Emission Tomography/methods , Psychiatric Status Rating Scales , Supranuclear Palsy, Progressive/complications , Supranuclear Palsy, Progressive/diagnostic imagingABSTRACT
To correlate cerebral histopathological and immunohistochemical changes in the neuroclinical features of the AIDS dementia complex (ADC), autopsy results of 28 ADC patients were related, in a retrospective analysis, to scores on a standardised neurological examination performed at neurologic onset. From a histopathological point of view, the cases were classified as follows: 9 cases of HIV leucoencephalopathy (HIVL; diffuse myelin damage and rare microglial nodules), 7 cases of HIV encephalitis (HIVE; several microglial nodules and no myelin damage) and 12 cases of mixed HIVL and HIVE (HIVL-E). The groups differed significantly with respect to symptoms and CD4 count at neurologic onset, survival and neurological impairment. Immunohistochemically, the interstitial component (p24-positive cells scattered singly within the white matter) was significantly more prevalent in HIVL, and the micronodular component (p24-positive cells confined within microglial nodules) in HIVE. Neurological damage was worse in cases with a high prevalence of interstitial component or a low prevalence of micronodular component. HIVE, HIVL and HIVL-E are distinct clinical forms of ADC. Neurological impairment is related to white matter damage.
Subject(s)
AIDS Dementia Complex/pathology , AIDS Dementia Complex/physiopathology , Adult , Autopsy , Female , Humans , Immunohistochemistry , Male , Retrospective StudiesABSTRACT
The enantioselective synthesis of 2-amino-3-hydroxynorbornene-2-carboxylic acid derivatives (5) was studied using the Diels-Alder reaction between cyclopentadiene and different dienophiles, i.e., alkyl 5-oxo-2-phenyloxazol-4-methylenecarbonates (1) or 2-benzoylamino-3-alkoxycarbonyloxy-acrylates (12), operating with different Lewis acids and both with thermal and with ultrasound conditions. The enantioselective synthesis of the exo/endo compounds 5c,d and 5'c,d was achieved starting from the chiral menthyl acrylates 12b,c using Mg(ClO(4))(2) as the catalyst and ultrasound. The cycloadducts were obtained in very good yield, in mild conditions, in short time, and in good diastereomeric excess (exo, 80%; endo, 87%). Finally, the use of alkylidene-oxazolones or acrylates and EtAlCl(2) or Mg(ClO(4))(2) as the catalyst allowed control of the cycloaddition reaction in favor of the exo or endo products.
ABSTRACT
Recently a series of 2-amino-5-sulfanyl-1,3,4-thiadiazole derivatives bearing different substituents were synthesized and screened pharmacologically in order to evaluate their central nervous system activity. The purpose of this study was to evaluate the effects of the title compounds on CNS activity by varying the substituents in the thiadiazole moiety. It was found that some of these compounds possess marked antidepressant and anxiolytic properties comparable in efficiency to the reference drugs Imipramine and Diazepam. The most potent compound 3k was further investigated to complete its pharmacological profile with respect to undesired side effects. Behavioral results showed that 3k is a very promising compound, characterized by a mixed antidepressant-anxiolytic activity accompanied by a therapeutic dose range that is essentially 2 orders of magnitude less than that at which side effects such as sedation and amnesia are evident.