We have searched for interstellar conformer I glycine (NH 2 CH 2 COOH), the simplest amino acid, in the hot molecular cores Sgr B2(N-LMH), Orion KL, and W51 e1/e2. An improved search strategy for intrinsically weak molecular lines, involving multisource observations, has been developed and implemented. In total, 82 spectral frequency bands, in the millimeter-wave region, were observed over a 4 yr period; 27 glycine lines were detected in 19 different spectral bands in one or more sources. The rotational temperatures derived from '' rotation diagrams '' are 75 þ29

Arcsecond-resolution spectral observations toward the protobinary system IRAS 16293-2422 at 344 and 354 GHz were conducted using the Submillimeter Array. Complex organic molecules such as CH 3 OH and HCOOCH 3 were detected. Together with the rich organic inventory revealed, it clearly indicates the existence of two, rather than one, compact hot molecular cores ( 400 AU in radius) associated with each of the protobinary components identified by their dust continuum emission in the inner star-forming core.

We have mapped the SiO J p 5-4 line at 217 GHz from the HH 211 molecular outflow with the Submillimeter Array (SMA). The high-resolution map (1Љ .6 # 0Љ .9) shows that the SiO J p 5-4 emission comes from the central narrow jet along the outflow axis with a width of ∼0Љ .8 (∼250 AU) FWHM. The SiO jet consists of a chain of knots separated by 3Љ-4Љ (∼1000 AU), and most of the SiO knots have counterparts in shocked H 2 emission seen in a new, deep VLT near-infrared image of the outflow. A new, innermost pair of knots have been discovered at just ‫2ע‬Љ from the central star. The line ratio between the SiO J p 5-4 data and the upper limits from the SiO J p 1-0 data of Chandler & Richer suggests that these knots have a temperature in excess of 300-500 K and a density of (0.5-1) # 10 7 cm Ϫ3 . The radial velocity measured for these knots is ∼30 km s Ϫ1 , comparable to the maximum velocity seen in the entire jet. The high temperature, high density, and velocity structure observed in this pair of SiO knots suggest that they are closely related to the primary jet launched close to the protostar.

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We have searched three hot molecular cores for submillimetre emission from the nucleic acid building block pyrimidine. We obtain upper limits to the total pyrimidine (beam‐averaged) column densities towards Sgr B2(N), Orion KL and W51 e1/e2 of 1.7 × 1014, 2.4 × 1014 and 3.4 × 1014 cm−2, respectively. The associated upper limits to the pyrimidine fractional abundances lie in the range (0.3−3) × 10−10. Implications of this result for interstellar organic chemistry, and for the prospects of detecting nitrogen heterocycles in general, are discussed briefly.