A study of certain reactions of 4-chloro-6-methylhydrazino-5-nitropyrimidine and the 4-methoxy and 6-dimethylamino analogs

The reaction between 4- chloro- 6- methoxy- 5-nitropyrimidine and methylamine was investigated. The reaction product was identified as 4-methoxy-6-methylamino-5-nitropyrimidine from synthesis of the product via 4-chloro-6-methylamino-5-nitropyrimidine. The product was the result of displacement of chloro substituent with methylamine. The reaction occured under mild condition (e. g. 15-20 C. in dioxane). Reaction of 4-chloro-6-methoxy-5-nitropyrimidine with methylhydrazine does yield product as a result of direct nucleophilic substitution. When the 4-methoxy-6-methylamino-5-nitropyrimidine was refluxed with methylhydrazine in absolute methanol to yield a product, carbon-hydrogen-nitrogen analysis of this substance indicated that the compound was 4-methylamino-6-(l-methylhydrazino)-5-nitropyrimidine. During the course of a study involving the preparation of certain derivatives, 4-dimethylamino-6-methoxy-5-nitropyrimidine or 4-methylhydrazino analog was refluxed with methylhydrazine in pyridine there was no evidence of nucleophilic substitution of methoxy group; approximately 40% of starting material was recovered. The reason that 4-dimethylamino-6-methoxy -5-nitropyrimidine does not respond to direct nucleophilic substitution with methylhydrazine apparently stems from steric hindrance imposed by the methylhydrazine substituent. Among the effects caused by the steric crowding is the forcing of the nitro substituent out of the plane of the pyrimidine ring thus losing the important resonance contribution of the nitro substituent in making the 4- and 6-positions more electrophilic. The it spectral data are included for all previously unreported compounds which were prepared

24-2646

Abstract. Four hundred and forty-one blood and serum samples were collected during August to October 1998 from the blood donors at the blood bank of Rajvithi Hospital, Bangkok, Thailand. Their ages were varied between 18-55 years. All specimens were tested by immunostaining and ELISA methods. Forty-seven specimens (10.66%) gave positive results by immunostaining. Among these, 20 cases were seropositive and 27 cases were seronegative. The age group between 41-50 years had a high percentage of CMV infection as judged by the immunostaining method, more than the other age groups. By ELISA, 231 cases (52.38%) had positive IgG antibody to CMV, 42 cases (9.52%) were IgM antibody positive and 39 cases (8.84%) were positive for both IgG and IgM antibodies. The age groups between 36-40 years had a higher percentage of IgM antibody positives than the other age groups. Since the immunostaining method can detect early CMV infection, screening for the presence of antibodies alone is not enough to rule out CMV infection. Immunostaining along with ELISA detection of antibodies was useful for determining a decrease in CMV infection

11-3495

Abstract. The human immunodeficiency virus Tat regulatory protein is essential for virus replication and for the efficient transcription of HIV-1 provirus, and in the pathogenesis of AIDS. The role of the tat gene was investigated in 300 samples. It was found that 71.7% were subtype CRF_01AE, 9.3% were subtype B, while 11.7 and 7.3% of them were cross-reactive and non-typeable, respectively. Moreover the results from peptide ELISA also showed that a low CD4 cell count was related to a low anti-Tat antibody (p<0.05), which may be due to the progression of HIV-1, which can be found predominantly in AIDS patients. The results of nested PCR showed that the second Tat exon might also play a role in T-cell activation. Reverse transcription polymerase chain reaction (RT-PCR) was used to measure HIV-1 mRNA expression in PBMC. RT-PCR negative results were found mostly in the asymptomatic HIV-seropositive group (88%). HIV-1 mRNA expression was found to correlate with current immunologic status. The differences in Tat protein sequences from DNA sequencing between the patients who had anti-Tat antibody positive and anti-Tat antibody negative, were not significant (p>0.05). These results suggested that the Tat amino acid sequences were conserved among each group of samples and did not change significantly compared with the consensus sequence in previous studies. Several factors make Tat an attractive target for vaccine design

A prospective clinical and bacteriologic study of inguinal buboes in Thai men.

One-hundred thirteen men (mean age, 23 years) who presented with inguinal buboes to a government-operated hospital for sexually transmitted diseases (STDs) in Bangkok were studied between February 1987 and February 1989. The median duration of preceding symptoms was 7 days (range, 1-62 days). The majority of patients (74; 65%) had received treatment previously; 31 (27%) were febrile, 13 (12%) had extrainguinal lymphadenopathy, and 31 (27%) had concurrent active genital ulcers. There was no history of genital ulceration in 66 (58%) of the patients. Pus was obtained from 51 of the 110 buboes aspirated for culture; 21 (41%) of these cultures yielded Haemophilus ducreyi, and 2 (3.9%) were positive for Chlamydia trachomatis on immunofluorescence microscopy. Saline (1 mL) was injected and reaspirated from the buboes of 35 of the other 59 patients; 3 buboes yielded H. ducreyi and 9 were positive for C. trachomatis. All cultures for other aerobic and anaerobic bacteria and viruses in intact buboes were negative. Syphilis serology was positive in only one case. Patients attending STD clinics in this region who have large, fluctuant, edematous inguinal buboes containing pus should receive presumptive treatment for chancroid. If there is no pus, then the bubo is more likely to be caused by lymphogranuloma venereum