1',2'-seco-dideoxynucleosides as potential anti-HIV agents.

1',2'-seco-2',3'-Dideoxycytidine (12), -guanosine (14), -adenosine (16), and -inosine (18) were prepared from (R)-benzylglycidol as potential anti-HIV agents. When compared to ddAdo in protecting ATH8 cells, they were found to be inactive.

Adenosine deaminase inhibitors. Synthesis and biological evaluation of putative metabolites of (+)-erythro-9-(2S-hydroxy-3R-nonyl)adenine.

The synthesis and biological evaluation of three chain-hydroxylated (+)-erythro-9-(2S-hydroxy-3R-nonyl)adenine [(+)-EHNA] derivatives are reported. Hydroxy groups at positions 9', 8', and 8',9' (12, 25, and 16) were introduced by either epoxidation or hydroboration of a terminal olefinic intermediate. Affinities for calf intestinal adenosine deaminase (ADA) were determined from the steady-state inhibition of adenosine deamination. Ki values of 0.82, 3.8, 6.4, and 15.8 nM were estimated for (+)-EHNA, 9'-hydroxy-(+)-EHNA (12), 8'-hydroxy-(+)-EHNA (25), and 8',9'-dihydroxy-(+)-EHNA (16), respectively, by assuming a single class of binding sites. However, the data for all inhibitors conformed more closely to the kinetics of a heterogeneous system with different affinities for two or more binding sites. The fairly high potencies of 12 and 25 suggest that other substitutions at the terminal position of the nonyl chain could yield useful ADA inhibitors.

p-Aminoacetophenone as a reagent for the colorimetric determination of cerium(IV).

With a solution ofp-aminoacetophenone, cerium(IV) gives a purple colour which can be used for its detection and determination. The limits of identification and dilution are 1.0 mug and 1 in 50000 respectively. Beer's law is obeyed in the range 14-350 mug. The colour is stable for only 5 min and measurements of absorbance must be made quickly. The interferences are fewer than with existing methods.

Application of LC-MS/MS for the identification of a polar impurity in mosapride, a gastroprokinetic drug.

In the impurity profile of mosapride a polar impurity (0.1%) was detected in HPLC with respect to mosapride. Based on the mass spectral data obtained by LC-MS/MS analysis this impurity structure was characterised as 4-amino-5-chloro-2-ethoxy-N-[[(4-benzyl)-2-morphinyl] methyl] benzamide. It is interesting to note that this impurity is potent analogue of mosapride, which will have much higher gastroprokinetic activity than metoclopramide. This impurity was synthesised from an unambiguous route and confirmed the structure by collecting various spectral data and the formation is discussed. To our knowledge this compound was not reported as process impurity elsewhere.

Basidiobolus: An unusual cause of lung abscess.

Non-resolving pneumonia leading to lung abscess is always a challenge to the treating physician especially in a diabetic patient. Atypical radiological features of lung abscess should raise the suspicion of unusual organisms. This is a case report of a 42 year old diabetic male presented with features suggestive of lung abscess and multiple target organ damage. Subsequent work up revealed that the etiological agent is a rare fungus - Basidiobolus. To the best of our knowledge this is the first case of Basidiobolus lung abscess reported from India.